current process benchmark for the last planner...

GlennBallard&IrisTommelein(2016).CurrentProcessBenchmarkfortheLastPlannerSystem.Availableatp2sl.berkeley.edu

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CurrentProcessBenchmarkfortheLastPlannerSystem

GLENNBALLARD1&IRISTOMMELEIN2

1ResearchDirector,ProjectProductionSystemsLaboratory,UniversityofCalifornia,[email protected],ProjectProductionSystemsLaboratory,UniversityofCalifornia,[email protected]


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OutlineoftheCurrentProcessBenchmarkfortheLastPlannerSystem

A. P2SLCurrentProcessBenchmarks

B. WhyLastPlanner?-aBriefHistory

C. Functions

D. PresuppositionsandConventions

E. Principles

F. Processes

G. Methods

H. Implementationa. Designb. Deployment

I. FutureResearch

J. FrequentlyAskedQuestions

K. Acknowledgements

L. Glossary

M. LastPlannerPublications


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A.P2SLCurrentProcessBenchmarksTheUniversityofCaliforniaBerkeley’sProjectProductionSystemsLaboratory(P2SL)periodicallypublishesadescriptionofthecurrentbenchmarkineachprojectmanagementprocessthatisasubjectofresearch.ThisreportsonthecurrentbenchmarkfortheLastPlannerSystem(LPS)forprojectproductionplanningandcontrol.Currentprocessbenchmarksaredevelopedwithindustrypractitionerstobestincorporatethelatestadvancesinboththeoryandpractice.Consistentwiththeleanphilosophyofcontinuousimprovement,eachpublicationofaprocessbenchmarkincludesadescriptionoftheresearchneededtosurpassit.WeunderstandLPS,attheleveloffunctions,presuppositions,principlesandprocesses,tobeaspecificationforprojectproductionplanningandcontrol--notaspecificwaytoplanandcontrolproductiononprojects,buttherequirementsanyspecific‘way’mustmeetinordertobevalid.Thatsaid,thisbenchmarkcanbeunderstoodasa“CurrentBenchmarkforProjectProductionPlanningandControlSystems”.Wedonotwanttobeoverlyprescriptiveinourdescriptionofanymanagementprocess,includingLPS,bothbecausewedonotwanttodiscourageexperimentationandbecauseitisimpossibletospecifyexactlywhatneedstobedoneineverypossiblecontext.OurgoalistobesufficientlydescriptiveoftheSystemsothatuserscanunderstanditsfundamentals;namely,functions,presuppositions,principlesandprocesses,andsobebetterabletospecifymethodsandtoolstoaccomplishthefunctionsconsistentwiththesefundamentals.Tothatend,inthefollowingwefirstprovideabriefhistoryofthedevelopmentoftheLPS,explainingwhyitwasinventedandwhyitisneeded.ThesubsequentsectionsdescribethefunctionsLPSisdesignedtoperformanditspresuppositions(what’sheldtobetrueabouttheworldinwhichfunctionsaretobeperformed),Fromthese,principles(behavioralguidelinesforexecutingfunctionsgiventhepresuppositions)areinferred.Nextprocessesaredescribedtoexplainhowthefunctionsarelinkedtogethertomakeasystem,andfinallywedescribethemethodsusedtoperformthefunctionswithinprocessesconsistentlywithpresuppositionsandprinciples.


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Recognizingthatastandardpracticemustextendtotheleveloftools,andthateachorganizationneedstohavestandardsforprojectproductionplanningandcontrol,welisttheelementstobespecifiedindevelopingastandard.(SeethesectionbelowonImplementation).Readersofthisdocumentmaycomeatfromdifferentangles.ThestructurewasestablishedforreaderswhowanttohaveasufficientunderstandingregardingtheWHATandWHYoftheLastPlannerSystemtobeabletomakereasoneddecisionswhethertoembraceit,ortoevaluatetheirownimplementationsoftheSystem.ThoselookingmoreforHOWtodoitmaywanttofirstreadSectionsF,G,HandK(Processes,Methods,DesignandDeployment,andFrequentlyAskedQuestions),thenreturntotheremainingsections.WeunderstandthattheLastPlannerSystemcanandisbeingusedinavarietyofapplications,butinthiswork,weassumethatitisappliedinaconstructionproject,bothindesigningandconstructing.Methodsusedonlyindesigningorconstructingaretaggedassuch.Aglossaryoftermsislocatedattheendofthisdocument.Termsintheglossaryareitalicizedonfirstuse.

B.WhyLastPlanner?Adistinctioniscommonlymadebetween‘planning’,inthesenseofdesigningwaystoachieveobjectives,and‘control’,puttingplansintoactiontocauseobjectivestobeachieved.TheLastPlannerSystem(LPS)wascreated,intheearly1990s,asasystemforprojectproductioncontrol.Productioncontrolwasthoughttobeamissingpieceinanotherwisecompleteprojectmanagementtoolkit,whichwasdominatedbyprojectcontrols.Thejobofprojectcontrolsistosetcostandscheduletargetsinalignmentwithprojectscope,andtomonitorprogresstowardthosetargets.Thejobofproductioncontrolistosteertowardtargets;todowhatcanbedonetomovealongtheplannedpath,andwhenthatbecomesimpossible,tofigureoutanalternativewaytoachievetargets.

Bothareneeded.Theyaretwosidesofacoin.Projectcontrolswithoutproductioncontrolislikedrivingwhilelookingintherearviewmirror.Productioncontrolwithoutprojectcontrolsislikedrivingwithnodestinationandnoawarenessofremainingdistanceorfuel.TheinitialequationofLPSwithproductioncontrolhaschangedovertime.Growingawarenessoftraditionalscheduling’sfailuresinsettingdetailedtimeandcosttargetsprovokedpartialadditionofthatfunctiontoLPSinthelate1990s;“partial”becausepullplanningmaybeusedtodetailplansateveryleveloftaskbreakdown,


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butprojectcostandscheduletargets(budgetsandcompletiondates)aresetoutsidetheLastPlannersystem.TheinspirationforLPSwasthediscoveryofchronicallylowworkflowreliabilityinconstructionprojects.Consequently,thefirststepinitsdevelopmentwastoimproveworkflowreliability,toincreasethematchbetweenDIDandWILL;i.e.,tolearnhowtodowhatwesaywe’regoingtodo.Beginningintheearly1990s,thatwasdonethroughmeetingswithfrontlinesupervisorstoproducecoordinatedweeklyworkplans,followingtheruletoincludeonweeklyworkplansonlytasksthatarewelldefined,sound,sequenced,andsizedtoperformercapabilities3.Thatwassuccessful.PercentPlanComplete(PPC)improvedasdidlaborproductivity.ButitalsobecameapparentthatPPCcouldbe100%,productivityexcellent,andaprojectstillbefallingbehindschedule.RecognizingthatprojectprogresstowardscheduledcompletiondatesrisesandfallswithPPConlywhentasksaremadereadyintherightsequenceandrate4,alookaheadplanningprocesswasaddedtoLPSsowhatSHOULDbedoneCANbedonewhenneeded5.Oncelookaheadplanningwasinplace,bothprojectcostandscheduleperformanceimproved,butitbecameapparentthatschedulingcouldbedonebetter.Toooften,whatSHOULDbedoneaccordingtotheprojectscheduleeithercouldnotorshouldnotbedonetobestaccomplishprojectobjectives.ThistookLPSbeyonditsoriginalproductioncontrolfunctions.Onceeffectivelookaheadplanningrevealedtheinadequacyofscheduling,pullplanningwasaddedtoLPS,initiallytodetailthemilestone-levelmasterschedule,phasebyphase(reversephasescheduling).Sooncollaborativepullplanningcametobeusedtoateveryleveloftaskbreakdown:project(masterschedules),phase,process,operationandstep.

3Seee.g.Ballard&Howell,1998.4Whetherornottherateofprogressisadequateisafunctionoftheamountofcapacityrelativetodemand.SeePresuppositionsbelow.5LookaheadplanningwasdoneinconstructionwellbeforeLastPlanner,buthastendedtobeadropoutfromahigherlevelschedule,assumingthatalltaskswillbefullysoundandcapacitytoperformthemwillbesufficient.Assuch,traditionallookaheadplanningservedasanearlywarningofmobilization—‘You’regoingtostartthewallsinthebasementthreeweeksfromnow,right?’.Thisisnotaquestiontowhich“no”isanacceptableanswer!ThelookaheadplanningprocessintheLastPlannerSystemhasthejobofidentifyingandremovinganyremainingconstraintsonscheduledtasksinthelookaheadperiod.Ifconstraintscannotberemoved,thetaskisrescheduledforalaterdatewhenconstraintswillhavebeenremoved.


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LastPlannerSystemInsightsThroughtheyears,reflectiononimplementationexperienceshasproducedimportantinsights.Hereareafew;someofwhich,likethefirstbelow,weregreatlyinfluencedbythethinkingofothers:

• Topreventreoccurrenceofbreakdownsrequiresunderstandingwhathappened.Thatincludesunderstandingwhypeopledidwhattheydidinthecircumstancesastheyexperiencedthem.Ifpeoplefearpunishment,theywillnotparticipateinthesearchforcausesandcountermeasures.(SeeDeming,1986;Dekker,2006)6

• Thereisalwaysatrade-offbetweentimeandcost,butthelevelatwhichthetrade-offismadechangeswithworkflowreliability,andLPS,properlyimplemented,improvesworkflowreliability.7

• TheprinciplesofLPSapplytoalltypesofworkthatrequirecoordinationbetweenhumans.

• Fromtheperspectiveofcontinuousimprovement,LPS’sjobistostabilizeoperationssotheycanbefurtherimproved,bothindividuallyandintheprocesseswhichtheycomprise,butitalsoimprovesproductivity.Many,perhapsmost,peoplearesatisfiedwiththatanddon’texploittheopportunityformorefundamentalimprovementinperformance.

• Theindustryunknowinglyplansforproductivityatapproximately50%PPC.(Liu,etal.,20108)

• 5WhysAnalysisispracticalandbringsunexpectedbenefits,especiallywhendataisstoredandmined.

• Workstructuringprecedesproductioncontrolandculminatesinschedules.Location-basedworkstructureshavebeensuccessfullycombinedwithLast

• Plannersystemproductioncontrol,whichwasdoesnotpresupposeanyspecificworkstructure9.

6Deming,W.E.(1986).Dekker,S.,2006.7Queuingtheoryunderliesthisphenomenon,whichiswellillustratedintheProductionFlowGraph,Figure3-17inFactoryPhysicsforManagersbyPoundetal.Simplystated,ascapacityutilizationapproaches100%,waittimeaccelerateswithoutend.ApplicationtoLPSwasmadeinHowelletal.,2001.8AcorrelationanalysisbetweenlaborproductivityandPPCisreportedinLiuetal.(2010).Whentheequationforthelineofbestfitforthatdatasetisdetermined,substitutionofaPPCvalueof50%inthatequationyieldsaperformancefactor(theratioofactualtobudgetedproductivity)equalto0.98(fromunpublishedlecturesbyGlennBallard).9Locationbasedworkstructures(includingtakttimeplanning)havebeensuccessfullyusedwithLPS.Totheextentthatreliablereleaseoflocations(taktzones)isachieved,thatsimplifies


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• Currently,thethreeleastimplementedcomponentsofLPSaredesignofoperations,measurementoflookaheadplanningperformance,andlearningfrombreakdowns.Manyonlydoweeklyworkplanning.Someonlydocollaborativephaseplanning.LPSisasystemofinterconnectedparts.Omissionofapartdestroysthesystem’sabilitytoaccomplishitsfunctions.

C.WhatarethefunctionsoftheLastPlannersystem?Functionsaretheproperworkofthesystem;itsjobs.

1) Specifyingwhattasksshouldbedonewhenandbywhom,frommilestonestophasesbetweenmilestones,toprocesseswithinphases,tooperationswithinprocesses,tostepswithinoperations.

2) Makingscheduledtasksreadytobeperformed

3) Replanning/planningtocomplete,toachieveprojectobjectives

4) Selectingtasksfordailyandweeklyworkplans—decidingwhatworktodonext

5) Makingreleaseofworkbetweenspecialistsreliable6) Makingvisiblethecurrentandfuturestateoftheproject

7) Measuringplanningsystemperformance

8) Learningfromplanfailures10Many,perhapsallofthesefunctions,havebeenrecommendedbyothersinsomeformorfashion,butnever,toourknowledge,alltogetherinasinglesystem.Further,afewareperhaps(almost)unprecedented;e.g.,theexplicitfocusonmakingworkready,onworkflowreliability,specificationofselectioncriteriafortaskstobeplacedonnear-termworkplans,systemtransparency,andmeasurementofsystemperformance.

managementofflowsandshiftsthefocusfromcoordinatingworkbetweenspecialists(designsquadsorconstructioncrews)tocoordinatingworkwithinthosesquadsorcrews.SeeSeppanen,etal.(2015)andFrandsen&Tommelein(2016).10NB:Planningsystemperformanceandplanfailures(failurestosuccessfullyexecuteplannedtasks)mayresultfromcausesoutsidetheimmediatecontrolofthoseplanningandexecutingdesignandconstructiontasks.Thewholemanagementandexecutionsysteminfluencesperformance.Analyzingplanfailuresisonewaytorevealneedsandopportunitiesforimprovementinthelargersystem.


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D.PresuppositionsandConventionsPresuppositionsarewhatisassumedtobetrueabouttheworldinwhichtheproductionplanningandcontrolfunctionsaretobeperformed.Sinceproductionsystemsarebothsocialandtechnical,therelevantpresuppositionsconcernthesocial,thetechnical,ortheircombination.

A. Productionsystemsarebothsocialandtechnical.B. Allplansareforecastsandallforecastsarewrong.Forecasterrorvarieswith

forecastlengthandlevelofdetail.C. Planningisdynamicanddoesnotenduntiltheprojectiscompleted.D. Involvingthosewhowilldirectlysuperviseorperformtheworkbeing

plannedresultsinbetterplansandgreaterabilitytoadaptplanswhenneeded.

E. Operationalperformance(safety,quality,timeandcost)varieswiththedegreeofplanningandpreparation.

F. Willingnesstoinvestinplanningandpreparationvarieswiththereliabilityofworkflow,thepredictablereleaseofworkfromone‘specialist’toanother.WorkflowreliabilityismeasuredbyPPC(percentplancomplete).Toillustratethepoint,supposePPCis40%.Thatdiscouragesfrontlinesupervisors(lastplanners)frominvestingtimeandenergyinplanningandpreparingtoperformtasksthatarelessthanacoinfliplikelytoturnupheads.Bycontrast,whenPPCis70-80%,frontlinesupervisorshaveabetterchanceoftheirplanningandpreparationpayingoff.

G. Makingcommitmentspublicallypromotescareinmakingcommitmentsandincreaseseffortstodeliveroncommitmentsthataremade.Italsoincreasescollaborationbetweentrades,willingnesstoshareassumptions,bestpathforward,coordinationandgeneralqualityofthework.

H. Theprobabilitythatcommitmentscanandshouldbekeptisincreasedwhenbothparties,customerandsupplier,practicereliablepromising—theytaketheirpromisesseriouslyandengageinaconversationtoaligntheinterestsandcapabilitiesofbothparties.

I. Anessentialprerequisiteforreliablepromisingisthatsupplierscansay“no”toarequestbyappealtotaskappropriateness(sequence),orreadinesstobeperformed(taskdefinition,soundness,orsizerelativetocapacityofperformers).

J. Actorswithinaprojectproductionsystemcanmakechoicesthathelporhinderachievingprojectobjectives;i.e.,actorshavediscretion.

K.


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L. Understandingprojectobjectivesandthecurrentandfuturestateoftheprojecthelpsactorsmakebetterchoices.

M. Perfectplanningmaynotbepossible,butitispossibletonevermakethesamemistaketwice.

N. Variationinproductionsystemscanbereducedbutnevereliminated,sobuffersarerequiredtoabsorbthatvariationandprotecttargets.11

O. Workflowreliability,asmeasuredbyPPC,riseswhencommitmentsaremadeonlytotasksthataresound,sequenced,andproperlydefinedandsized(SeePrinciple6below).

P. ProductivityrisesandfallswithPPC.Thelevelofproductivityincreaseordecreaseislimitedbytheextenttowhichcapacityexceedsdemand,resultinginlaborhoursnotexpendedonproduction.

Q. ProgressrisesandfallswithPPCtotheextentthattasksaremadereadyintherightsequenceandrate.Therateofincreaseordecreaseisafunctionoftheextenttowhichcapacityfallsshortofdemand.Iftherearefewerlaborhoursavailablethanneededtoperformscheduledtasks,thatwillreducetherateofprogressfromwhatitcouldhavebeen.

Conventionsareneithertruenorfalse.Thefollowingconventionisusefulwhentalkingaboutworkonconstructionprojects.

• Taskscanbebrokendownintomanydifferentlevelsofdetail.Lackingagenerallyrecognizedtaxonomyfortaskbreakdown,thefollowingisproposed:Projectsconsistofphases,phasesconsistofprocesses,processesconsistofoperations,operationsconsistofsteps,andstepsconsistofelementalmotions12.

11Strictlyspeaking,variationofthetypementionedhereisoneoftwotypes.Buffersareappropriateforvariationthatcanbedescribedbystatisticaldistributions;whatmightbecalledthe‘predictablyunpredictable’.Anexampleisprocessingdurations.Anothertypeofvariationconsistsinlowprobability/highimpacteventsthatdisruptproductionsystems—‘emergencies’,‘blackswans’.Theymustbehandledbybuildingflexibilityintoplansandenablingteamresponsivenessandflexibility.NotethankstoHajnalkaVaagen,NTNU.12Motionanalysis,themethodofanalyzingworkermovementsintermsofelementalmotions(therbligs)wasdevelopedbyFrankGilbrethintheearly1900’s.Therbligsisajumbleofthelettersinhislastname.Elementalmotionsarewhatrobotsareprogrammedtodo;e.g.,grasp,lift,rotate.Motionanalysisisnotyetvisibleinconstruction,butmayfirstappearasroboticsareintroducedinfabricationshops.


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E.PrinciplesandRulesPrinciples(alsocalledrules)areguidestoactingintheworldtoperformproductionplanningandcontrolfunctionsconsistentwiththepresuppositionsabouttheworld.

1. Keepallplans,ateverylevelofdetail,inpublicviewatalltimes.2. Keepmasterschedulesatmilestonelevelofdetail.3. Planingreaterdetailasthestartdateforplannedtasksapproaches.4. Produceplanscollaborativelywiththosewhoaretodotheworkbeing

planned.5. Re-planasnecessarytoadjustplantotherealitiesoftheunfoldingfuture.6. Revealandremoveconstraintsonplannedtasksasateam.7. Improveworkflowreliabilityinordertoimproveoperationalperformance.8. Don’tstarttasksthatyoushouldnotorcannotcomplete.Committoperform

onlythosetasksthatareproperlydefined,sound,sequencedandsized.9. Makeandsecurereliablepromises,andspeakupimmediatelyshouldyou

loseconfidencethatyoucankeepyourpromises(asopposedtowaitingaslongaspossibleandhopingsomeoneelsespeaksupfirst).

10. Learnfrombreakdowns(unintendedconsequencesofactionstaken).11. Underloadresourcestoincreasereliabilityofworkrelease.12. Maintainworkablebacklog;abacklogofreadywork(tasksreadytobe

executed)tobufferagainstcapacityandtimeloss.

F.ProcessesInthissection,weusetwodiagramstoshowtherelationshipbetweenlevelsofplanningandthevariousfunctionsperformedateachlevel.ThestructureofthediagraminFigure1isbasedonShould-Can-Will-Did.MasterandphaseschedulesspecifywhatSHOULDbedonewhenandbywhom.ThejoboflookaheadplanningistomakescheduledtasksreadysotheyCANbeperformedwhenscheduled.Commitmentplansareformedbyselectingfromreadywork,expressingwhatWILLbedoneintheplanperiod.Planfailures(akabrokenpromises)areidentifiedbycomparingDIDtoWILL,thenanalyzedinsearchofcountermeasurestopreventreoccurrence.Themethodsandmetricsusedtoperformthesefunctionsarelistedontherighthandsideofthediagram.SeetheglossaryfordefinitionsofPercentPlanComplete(PPC),TasksMadeReady(TMR)andTasksAnticipated(TA).


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Figure1:SHOULD-CAN-WILL-DID

Figure2showshowonelevelofplanningfeedsthenext.Function#1occursatthesetaskbreakdownlevels:project,phase,process,andoperation.Themasterscheduleisexpressedinphases.Thephasescheduleisexpressedinprocesses.Thelookaheadscheduleisinitiallyexpressedinprocesses,butaftertaskbreakdown,thelookaheadscheduleconsistsofoperations.Operationsdesigns(howtheyaretobeperformed)areexpressedinstepstobecarriedoutbyindividualsorteams.Note:theworkplanthatimmediatelydrivesproductionistheproductofselectionfromeligibletasksinworkablebacklog.Thetasksincommitmentplansareoperations.Executionofoperationsinaccordancewiththeirdesigniscontrolledbythefrontlinesupervisor(lastplanner)andthoseexecutingthework.


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Figure2:RelationshipsbetweenplanninglevelsintheLastPlannersystem

G.Whatmethodsareusedtoaccomplishfunctions?

Methodsandtoolsareproductsofinventionandarejudgedbytheirconsistencywithprinciplesandutilityinperformingfunctionswithinspecificcircumstances.WalterShewhartinventedPlan-Do-Check-Actinthe1930s13.Morerecently,pull

13SteveWardconteststhisexplanation:“Hedidnot.Shewhart’soriginalversionwas“specification,production,inspection”ThiswasadaptedintoPDSAandtaughtbyDemingtotheJapaneseinthe1950’s.JUSEformedatranslationoftheconceptintoPDCA.Deminglater(1980’s)declaredthatPDCAwasa“corruption”oftheoriginalconceptandsaidthe“ShewhartCycle”shouldbePlanDoSTUDYAct.”


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planningwasadaptedfromearliercollaborativeplanningapproaches.Thetaxonomyofferedherefortaskbreakdownwasinventedtoprovideastandardlanguagetodistinguishbetweenlevelsofdetail.Itisreasonabletoexpectthatinventionswillcontinuetoemerge,andwhenthathappens,thisCurrentProcessBenchmarkforLPSwillbemodifiedaccordingly.Whatfollowsarethebest,provenmethodsofwhichwearecurrentlyaware.Wefirstlistthemethods,thendescribeeachmethod.

a) ForspecifyingShoulda. Pullplanning

b) Forlookaheadplanning/makereadya. Constraintsanalysisandremovalb. Taskbreakdown:Commitmentsaremadetoexecuteoperationstothe

conditionsofsatisfactionofimmediateandultimatecustomers.Scheduledtasksarebrokendown,asneeded,intooperations.

c. Collaborativedesignofoperations--whatstepsinwhatsequenceperformedbywhomusingwhat:

i. Virtualprototypingii. Physicalprototyping(constructionoperations)iii. FirstRunStudies

c) Forincreasingworkflowreliabilitya. Reliablepromising–Disciplinedapproachtocommitmentmakingin

whichbothrequesterandperformerinteractinconversationtoensureitiscleartobothwhatisbeingrequested--whatistobedonetowhatconditionsofsatisfaction(e.g.,timeofcompletion).

b. Visualcontrolsc. Underloadingresourcesd. Dailyhuddles

d) ForLearningfromPlanFailuresa. Analysisofbreakdownstounderstandwhytheyoccurredandto

identifythelevelofcauseatwhichcountermeasurescanbeeffectiveinpreventingreoccurrence.

b. PDCA:Plan-Do-Check-Actc. DCAP:Detect-Correct-Analyze-Prevent

e) Metricsa. PercentPlanComplete(PPC)b. TasksMadeReady(TMR)c. TasksAnticipated(TA)d. FrequencyofPlanFailures

PullPlanning


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PullPlanningisatechniquethatisusedaspartofLPStodevelopaplanfordoingworkatanyleveloftaskbreakdown,oneofwhichisaPhaseSchedule(ThelevelsareProject,Phase,Process,OperationandStep).PullPlanningcanbeusedtoplanworkinanytimehorizon,ortosequenceactivitiesaspartofaproductionplan.Useofpullplanningtoproducephaseschedulesshouldoccuratleastonelookaheadperiodaheadofscheduledstartsotaskscanbemadeready.Lookaheadperiodstypicallyrangefrom3to12weeks,dependingontheleadtimeneededtoremoveconstraints(seeitemDinFrequentlyAskedQuestions).Pullplanningsessionsshouldinvolveallwhoareresponsiblefordeliveringtheworkandwithauthoritytomakedecisions,plusotherswhocanprovideneededinformation;e.g.,safety,quality,logistics,auditoryengineeringspecialists.Oneofthekeystoasuccessfulpullplanistohavethoseexpertscollaborativelyworkingtogethertodevelopthesequenceofactivitiesthatproducesanacceptableworkflow.Pullplanninginvolvestheidentificationanddefinitionofthemilestone,orkeyeventthattheteamwillbepullingto;e.g.,releasingsubsequentworkactivities.Identifyingtheconditionsofsatisfactionofthemilestoneiscriticaltoasuccessfulpullplan.Toassurethatsharedunderstanding,thefirststepinpullplanningistoco-createwiththeteamadescriptionofthemilestonefromwhichtopull—what’sincludedandexcluded,whatworkitreleases,etc.Thecompletionofonemilestonesetsthestageforthebeginningofanotherone.Afterthemilestoneorkeyeventisclearlydefinedandtheconditionsofsatisfactionareagreed,theteambeginstoworkbackwardsfromit.Stickynotes(physicalorvirtual)arepostedbyperformersandrequestsaremadeofotherperformersforprerequisitetasks.Performersnegotiatetheconditionsofsatisfactionforthehand-offsbetweenthetasksposted.Participantsmustdeeplyunderstandtheirownwork,andalternativewaysofcarryingitout,inordertobeabletodevelopthebestplanforallpartiesinvolvedintheworkbeingplanned.AsnotedbySteveWard,thisisanareaofweaknesswhenspecialtycontractorsareengagedlateintheprojectanddonothavesufficientunderstandingoftheworktocontributeeffectivelytoplanning.Whatsomeonereallyneedsmaynotbestated,andhavetobedrawnoutbyothersaskingquestions.Toooften,weaskforeverythingwhenweonlyneedonepartofitinordertoaccomplishourtask.Completingtheworkofonedisciplineortradecreatestheconditionsforotherworktobegin.Participantsalsohavetounderstandwhatconditionstheyhavetomeetinorderforthemtostarttheirownworksotheycanmakerequestsofothers.


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Whileahigherlevelpullplanmaybedevelopedforanentireprojectphase,unlesstheyarerelativelysimpleandshort,theremaybemultipledetailedpullplansdevelopedfordifferentareas,systems,ortimeperiods.Pullplanning,likeallplanning,issubjecttodifferencesbetweenassumptionsabouthowthefuturewillturnoutandwhatactuallyhappens.Oneadvantageofpullplanningisitcreatesateamabletorespondflexiblytosuchdifferences.

ConstraintsAnalysis&RemovalInordertoensuremosteffectiveandefficientuseofcapacity,theworkthatSHOULDbeperformedbyacertaindatemustbeavailabletobeperformed(CAN)withoutanyblockageorinterruption,i.e.,constraint.Constraintscanbeeitherphysical(availabilityofplotterbeforeprinting,rebarinstallationpriortoconcreteplacement)orinformational(soilsreportbeforefoundationdesign,engineeringdetailsbeforefabrication,permitbeforehazardouswork).Thesecanbeidentifiedaspartoftheprocess/operationsdesignorastheymanifestthroughouttheexecutionofaproject.ActivityDefinitionModelprovidesarobustframeworkinwhichtothinkthroughthisprocess.Responsibilityforremovingconstraintsisspreadthroughouttheteam.Typicallydesignsquadbossesandforemenofconstructioncrewsareresponsibleforhavinglaborappropriatelyskilledandinthequantitiesrequired.Constructionengineersmayberesponsibleforremovingdesigninformationconstraints;materialsmanagersformaterialconstraints,etc.Itisimportanttoidentifythedepartmentsandindividualswhowillbethego-toguysforeachtypeofconstraint.However,itisimportanttonotethatthetimingrulesforidentifyingaconstraintmaybeverydifferentfromresolvingit,especiallythoserelatedtodynamiccapacity.Resolvingtheconstrainttoofarinadvance(suchasadvancedeliveryofmaterial,equipment,orreleaseofdesign)mayendupgeneratingwork-in-processandinventorythatpreventseffectiveexecutionofworkandcreatespotentialrework(theverythingthatLPSisgearedtoimprove).

TaskBreakdownThetaskbreakdownconventionusedinLPSunderstandsprojectsascomposedofphases,phasesofprocesses,processesofoperations,andoperationsofsteps.(SeeGlossaryforanexample).Processesareconnectedworkperformed;e.g.,detail-fabricate-preassemble-deliver-install.Supposethelookaheadwindowonaproject


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issixweeks,atwhichtimeidentificationandremovalofconstraintsbegins.Someconstraintsmayapplytoalloperationswithinaprocess;e.g.,materialsandinformation,whileothersarespecifictoindividualoperations.Thetransitionfromprocessestooperationsshouldoccurnolaterthan3weeksaheadofthescheduledstartdateforatasktoallowtimeforoperationsdesignandidentificationandremovalofconstraintsthatarerevealedbythatdesign;e.g.,specificskillsandpermitsneeded,locationandtypeofequipment,etc.

CollaborativeDesignofOperationsOnefundamentalelementofLPSistheinvolvementofthelastplanners,so-calledbecausetheirplansdirectlydriveexecution,asopposedtoservingasinputstootherplanningprocesses.Thesefrontlinesupervisorsaremostknowledgeableabouthowtooptimallyexecutetheworkwithinthegivenenvironment.Designofoperationsisanotherapplicationforpullplanning,andinvolvesnotonlythelastplanners,butalsothecraftworkerswhoaretoexecutethefirstinstanceoftheoperation(firstrunstudy),higherlevelsupervisorsinthechainofcommand,andspecialistsformaterialsourcing,designbuildability,quality,safety,logistics,equipment,etc.

ReliablePromisingAllworkgetsdonethroughlanguageandinthewaypeoplespeak,listenandcollaboratewitheachother.Reliablepromisesaretheresultofthecommitmentswemaketoeachotheroutofrespectforeachother'sconcerns.

Projectsareanetworkofcommitments.Projectsextendwellbeyondthesite,evenwhentheyhavereachedtheconstructionphase.Consequently,commitmentsaremadebetweenindividualsinthevariousorganizationsonandoffsite.

Beforemakingthepromise,theperformermakesareasonedassessmentoftheircapabilityandcapacitytoactontherequestwithintherequestedtimeframe.Afundamentaltenetofreliablepromisingistheacceptanceof“No”asanappropriateresponsetoarequest.Forexample,lastplannersmakereliablecommitmentstofollowingdisciplinesortradestocompletespecificworktasksbyaspecifictimeduringthenextworkcycle.Priortomakingthecommitment,thelastplannerconfirmsthatthetaskiswelldefined,issound–hasnounresolvedconstraint,isinpropersequence,andisappropriatelysized14.Thesecommitmentsaredocumented

14Seetasksequence,tasksoundnessandtasksizeintheGlossary.


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onthecommitmentplan.LastplannersandothersmakecommitmentstoattendLPSmeetingsandtocomeprepared.

Peopleintheextendedprojectnetworkalsorespondtotherequestsofothers.Inorderforsomeonetosayyestoarequesttheymusthavetheabilitytosayno.Iftheycannotsaynotoarequest,thentheycannotmakeapromise.Thisisahugeculturalchangefromtraditionalpracticeandrequirespersistentandpersuasivecoachingtobothmakethechangeandtosustainit.

InLPS,promisesaredocumentedinavarietyofways;forexample,inthepullplan,constraintlog,theweeklyworkplan,insupplier’scommitmentstodeliveratacertaintime,infabricator’scommitmentstomanufacturetoagreedspecifications,etc.

VisualControls

Thepurposeofavisualcontrolforaproductionsystemistoprovideclearvisualindicatorsdepictingthestatusofthesystematanappropriatelevelfortheaudiencetoachievesharedunderstandingsothatnecessaryactionscanbetaken.Thereforeavisualcontrolforaproductionsystemmustconveyinsimplevisualcues(1)appropriatemeasurements(notprojectcontrols),(2)up-to-dateinformation(notprint-outoflastweek’sinformation),or(3)what’sreallypossible(notascheduleprintedonthewall).Simplegraphsandchartspostedinpublicplacescanbeveryeffective.

Modernproductionsystemsutilizesensorstoprovidereal-timeinformationandoftentimesprovidedirectaccesstomechanismstoaddressanyvariationsintheproduction.

DailyHuddlesBrief,typicallystand-up,meetingseachdaybygroupsofinterdependentplayers,atwhicheach,inturn,shareswhatcommitmentstheyhavecompleted,whatcommitmentstheyneedhelpwithorcannotdeliver.Thiscanbedonewithinadesignsquadorconstructioncrew,andbetweenfrontlinesupervisorsofdesignsquadsorconstructioncrews.

CountermeasuresAnalysisofbreakdownsisdonetofindcountermeasuresexpectedtocompletelyorpartiallypreventreoccurrenceofthebreakdown.Often,theinitialreasonprovidedforanincompletetaskdoesnotprovidesufficientinsightintowhythetaskwasnotdone. Itmayrequireseveral interviews toget toeffectivecountermeasuresusingthe5Whystechnique.


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Timely generation and implementation of countermeasures reduces accidents,rework,andplanfailures.Thereturnoninvestmentmakesthissomethingeveryoneshoulddo,andallocatingcapacityforsuchanalysisisavitalmanagementact.Capturingreasonsforbreakdownsovertimeprovidesteamswithtrends,whichcanbeused todevelopstrategies toprevent re-occurrenceof the same failures in thefuture.Itshouldnotbea“blameandshame”toolorbeusedasaweapon.

CountermeasuresdevelopedthroughanalysisofbreakdownsaretestedusingPlan-Do-Check-Act.PDCAwasdevelopedbyWalterShewhartatBellLabsinthe1930s,andpopularizedbyhisstudent,W.EdwardsDeming.SometimesPDCAisreferredtoastheDemingCycle.

Figure3:PDCA

PDCAisaroughandreadymethodofformulatingandtestinghypotheses,andisthetoolmostcommonlyusedtotesttheeffectivenessofcountermeasuresidentifiedthrough5Whysanalysisofplanfailures.Supposeacommitment,madetoremoveaconstraintonascheduledtaskintheproject’slookaheadplan,wasnotsuccessful,andthetaskhadtobedelayedandrescheduled.5Whysanalysisidentifiedtherootcauseasassumingthatsoilconditionswouldbethesameasonanearbyproject.Wemightproposethatpeopleoughtnottomakeassumptions,butthat’shardlyaneffectivecountermeasure.Forthesakeofthisillustration,supposethatthecountermeasureproposedwastoincorporateintodesignreviewsachecklistthatcalledforlistingallrelevantassumptionsandtheirbases.Thehypothesistobetestedis:If<checklist>,thenfewerunfoundedassumptions,andsofewerplanfailuresindesign.DevelopingthehypothesisisthePLANinPDCA.TheDOinPlan-Do-Check-Actistoperformoneormoreexperimentstoseeifthehypothesisissupported.CHECKischeckingtoseeifusingthechecklistreducesplanfailures,andACTisdeclaringthechecklistastandardrequirementandimplementingthatstandard.

Detect-Correct-Analyze-PreventAconnectedproblemsolvingcycleisDetect-Correct-Analyze-Prevent(DCAP).Thiswasformulatedprimarilywithqualitydefectsinmind,butappliesalsotoplan


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failuresandaccidents/nearmisses.TheideaistoDETECTbreakdowns(variationsfromtarget)ascloseaspossibletotheirorigin,totakeCORRECTiveactionsoproductioncancontinue,toANALYZEthebreakdowntorootcauses(perhapsusing5Whys),thendevelopandtestcountermeasuresinordertoPREVENTreoccurrence.Anexample:Supposeanerroronadrawingisdiscoveredafterthedrawinghasbeenissuedforfabrication,butbeforefabricationstarts.Thecorrectiveactionistostoptheuseofthatdrawing,collectallpreviouslyissueddrawings,correctanddistributethecorrecteddrawing.Thatenablesfabricationtoresume,butdoesnothingtopreventsimilarerrorsfromhappeninginthefuture,soananalysisofthebreakdownisneededinordertodiscoverwhyithappened.Analysisrevealsthatthedrawingswereissuedlate,andtheurgencyforspeedcontributedtotheerror.Countermeasurescouldbedevelopedforsuchsituations,butfurtheranalysisisneededtodeterminewhythedrawingswerelate.Eventuallyitisdiscoveredthatkeyvendordatawasdelayed,andacountermeasurewasdevelopedtoincorporatevendorsintoLPSandengagetheminthepracticeofreliablepromising.Aconstructionexample:Aconstructionworkerwasinjuredwhenstruckbyawrenchdroppedfromahigherelevation.Inthiscase,correctionconsistsinprovidingmedicaltreatmenttotheworkerandalertingtheworkareafromwhichthewrenchcamethattherehadbeenaninjury.Furtherspecificsdependonthesituation,butonelikelypossibilityistostopworkinareasbelowhigherworkuntilstepsaretakentopreventrepetitionoftheincident.TherelationshipbetweenPDCAandDCAPisshowninthefollowingdiagram:

Figure4:DCAP/PDCAcombinedcycles


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MetricsCurrently,therearefourestablishedmetricstomeasuretheeffectivenessofLPSimplementation:

·PPC·TA·TMR·FrequencyofPlanFailuresThefirstthreeofthesemetricsinvolvecomparisonoftasksetsindifferentweeksofthelookaheadwindow.Inthefigurebelow,asixweeklookaheadwindowisassumed,beginning6weeksaheadofscheduledstart.

1weekfromstart WeeklyWorkPlan6weeksfromstart 3weeksfromstart StatusedWeeklyWorkPlan

PercentPlanComplete(PPC)–PPCmeasuresworkflowreliability;i.e.,thepredictablereleaseofworkbetweenworkgroups.isgenerallytrackedonaweeklybasis.PPCcomparesthetasksthatwerecompleted(Week-1infigureabove)againstthetasksintheweeklyworkplanforthatweek(Week0).Attheendoftheplanperiod(day,week,shift,etc.),PPCiscalculatedasthepercentageofcompletedtasksrelativetothosethatwereplannedatthebeginningoftheweek.PPCcomparesthestatusedweeklyworkplan(Week-1)againsttheweeklyworkplan(Week0).

TasksMadeReady(TMR)–TMRisthesamemeasurementasPPC,onlydoneearlierinthelookaheadprocess,comparingtheweeklyworkplan(Week0)againstanearlierweekinthelookaheadwindow(Weekn).TMRmeasurestheabilityoftheteamtoidentifyandremoveconstraintsaheadofthescheduledstartofspecificworktasks.

TasksAnticipated(TA)–TAmeasuresthepercentageoftasksforatargetweekthatwereanticipatedinanearlierplanforthattargetweek.Theobjectiveofthisindicatoristoprovidearelativemeasureofhowwelltheteamisabletocausewhatisactuallygoingtohappenontheprojectwithinthenextfewweeks.Thisplanningabilityiscriticalbecausewithoutit,therightworkcannotbemadeready.

MeasurementofTAandTMRstartsbycomparingtasksetsatWeek1(thelastweekinthelookaheadwindowpriortoscheduledstart)againstthetasksetsatWeek0(theweeklyworkplan).SupposethetasksetatWeek1isABCDEandthetasksetintheweeklyworkplan(Week0)isACEFG.OnlyA,CandEappearinboth,soTMR=ACE/ACEFG=60%.FandGareintheweeklyworkplan,butwerenotinWeek1,soTA=FG/ACEFG=40%.

Week-1Week0Week1Week2Week3Week4Week5Week6


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AsTMRandTAapproach100%,measurementshiftstocomparisonofWeek0againstWeek2.HowfartoextendTMRandTAisanempiricalquestionatthispoint,aswearenotawarethatanyonehasevermeasuredbeyondWeek1.Notealsothattherecanbegoodreasonforchangingcommittedtasks;forexample,whenexternalconditionschange,makingitimperativeorbeneficialtochangecourse;orwhenconstraintsreappearthatwethoughthadbeenremoved.Ofcourse,wewanttolearnhowtopreventnegativechanges,butlearninghowtoaccommodatenecessarychangesoropportunitiesisequallyimportant.

FrequencyofPlanFailures–Asdiscussedabove(seePercentPlanComplete–PPC),duringexecutiontasksareannotatedastowhetherornoteachwascompletedwhenplanned.Thosenotcompletedwhenplannedareassignedtoacategorywhichdescribesingeneralthecauseoftheplanfailureorvariance.Forexample,someusualcategoriesduringconstructionare“OwnerDecision,”“Engineering/Design,”“Weather.”Thesecategoriesaregenerallyestablishedpriortothestartoftheprojectandreflectthebroadcategoriesofplanfailurethatmightbeexpectedduringexecutionofthistypeofproject.However,astheprojectevolvesthecategoriescanberefinedtobringaddedinsighttothecausesofplanfailure.Asplanfailuresoccur,afrequencychartisupdatedtovisuallyindicatetherelativefrequencyofeachcategoryofplanfailure.Whenfrequencyofspecificcategoriesofplanfailuresaretrackedovertime,itrevealstheextenttowhichrootcauseshavebeenidentifiedandcountermeasurestakentopreventreoccurrence.

Thesecategories,oftencalled“ReasonsforVariance”,areusefultoidentifyweaknessesinspecificsupportsystemsorflows.Forexample,recurrentproblemswithmaterialsmaysignalafailureinthematerialsmanagementinformationsystemorinsupplier/sitecoordination.Theactualsourceofplanfailureshastobediscoveredbyanalysis.Identificationofacategoryislikegivingbloodhoundsthesocksofalostchildinordertoputthehoundsonthescent.Categorizationwithoutanalysisdoesnotpreventreoccurrenceofplanfailures.

H.ImplementationThissectionhastwoparts.First,thedesignofaprojectproductionplanningandcontrolsystemisdescribed,thenthedeploymentofaprojectproductionplanningandcontrolsystemisdescribed.

DesignDuetotheinherentcomplexityofprojectproduction(multiplestakeholders,differentlocations,alternatesourcingoptions,etc.),themeansthroughwhichproductionisplanned,executed,controlledandimprovedmustbetailoredtothe


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typeofworkandworkersthatperformit15.Therefore,acookie-cutterapproachorreplicatinganotherproject’scontrolsystemshouldbeavoided.Theallowableamountofvariabilityintheproductionsystemandthecorrespondingallocationofbuffersshoulddeterminewhichcontrolprotocolstheproductioncontrolsystemshouldenableincludingthelevelofdetailandfrequencyofplanning,controlandfeedback.Inthisregard,theproductioncontrolsystemcanuseoneoracombinationofphysicalcontrol,software(controlsolutionsincludingsensors)andhumancontrol.Asisdonetopreventaccidents,wherepossible,theyareengineeredoutofthesystem.Whenthatisnotpossible,topreventhumanerror,softwareisusedtocontrolactions.Finally,wheredependenceonhumanjudgmentisnecessary,theproductionsystemisstructuredandmanagedtofacilitatejudgmentsthatadvancethesystemtowardsitsgoals.Whenerrorsaremade,thattriggersasearchforcountermeasurestopreventreoccurrence.LPSenablescontrolofworkexecutionbyprovidingthefunctions,principlesandprocesseseachindividuallastplannerinvolvedinthedeliveryofaprojectmustfollowinordertooptimallyachievethedesiredprojectobjectives.However,thisisnotdoneinisolation.Theconventionalschedulingsystemsetsthebaselinescheduleandmeasuresprogress.Thisbaselinescheduleandassociatedmilestonesserveasobjectivesforprojectproduction.Iftheyareflawed,thatcripplesproductioncontrol.Whenthishappens,teamseithertendtogiveuponLPSandreturntotraditionalbehaviors,orrecreatetheprojectschedulethemselvesusingpullplanning.Theroleofthelastplanneristoaligntheactionsofindividuals(craftworkersandknowledgeworkers)involvedintheprojecttodelivertheobjectives.Seenfromavaluestreamperspective,therelationshipofcraftworkersandknowledgeworkersaretypicallyintertwined,therefore,thedesignofLPSforagivenprojectmustincorporatebothtypesofwork.Inaddition,dependingonthetypeofproject,theamountofinherentvariabilityisvastlydifferent.Forexample,agreenfieldresidentialprojecttypicallyexperienceslessvariabilitythanaturnaroundprojectinarefinery,wherethescopeisexpectedtoconstantlychangebasedonwhat’sdiscoveredwhenequipmentisdismantled.Thepenaltiesofnotmanagingthesourcesandassociatedimplicationsofvariabilityalsodiffertremendously.Forexample,aweekdelayinturningarefinerybackonwillhavedirectimplicationsonrevenueandvaluationofthatcompany.Thesameamountofdelaytypicallyhaslessimplicationsfortheownerofresidences.Therefore,thefrequencyofcontrolandadjustmentduetovariability(re-planning)mustbealignedwiththetypeofwork.15“ContrastingProjectProductionControlWithProjectControls”,ProjectProductionInstitute2015


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Sincethepurposeofthephasescheduleistospecifythehandoffsandconditionsofsatisfactionbetweenprocesseswithinagivenprojectphase,planningneedstobeperformedsufficientlyaheadofthephasetoallowlookaheadplanningtobeeffectivelyperformedandwhenthereischangeinscopeorallocationofscope.Duringthecourseofexecutingthephaseplan,whenreplanningisneeded,theteamtriestorecovertotheoriginalphasescheduleassoonaspossible,butmayneedtoreplantheremainingworktocompletewithinthephasemilestone.Ifthatisnotpossible,theteamplanningthenextphasewillhavelesstimewithinwhichtoexecutetheirphaseofwork.Everyonedoeswhattheycantoholdthecompletiondate.

CriticalNotesonplanningwindows:lookaheadandcommitmentplanningThelookaheadisthemainmechanismusedtodeterminehowandwhatworkshouldbedonewhenbywhom.Toreiterate,theworkhereisnotlimitedtocraftorknowledgework,butthelookaheadshouldallowenoughtimetoidentifyandmanageengineering,fabricationand/ordeliveryofanylonglead-itemsthattheprojectteamneedstocoordinate.Therefore,ifthestrategyistodojust-in-timefabricationofcertainmaterial,theoptimalscenarioisthattheleadtimeassociatedwithfabricationanddeliveryshouldbelessthanthelookaheadoftheinstallation.Ifthestrategyistobuildinventoryofthematerialonsiteaheadoftheinstallationbasedonforecastedusage,thelookaheadwindowassociatedwiththatworkcanbeshortenedtocoverthedeliveryofthematerialtotheinstallationarea.Thewindowofcommitmentplanningalsomustvarybasedonthetypeofwork.Typicallyforknowledgework(suchasdesign),wherecycletimesforgeneratingoutputsaremorethanafewdays,thecommitmentplanningprocessshouldbeperformedweeklyorbi-weekly.Forcraftwork,whereworkcontentisgeneratedonadailyorshiftbasis,thecommitmentplanningprocessshouldbeperformedatthesamepace,dailyorbyshift.

DeploymentThedeploymentofLPSshouldincorporatethemeanstoassessifprojectteamsareperformingitsfunctions,andadoptingandusingitsprinciplesandprocesseseffectively.Ifthedeploymentapproachselectedforagivenprojectisknowledgetransfer,usersofLPScanbeassessedbasedonadevelopmentalframeworkthatincorporatesdevelopmentstagessuchasaware,understand,capableandmaster.Bydoingthis,theeffectivedevelopmentoftechnicalcompetencecanbemonitored.Inadditiontotechnicalcompetence,thelevelofcommitmenttotheeffortshouldalsobeassessedandmonitored.Attheend,commitmentisneededtodevelop


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technicalcompetence.Todothiseffectively,awholeapproachincludingfrequencyofassessmentsandassessmenttoolsmustbedevelopedandimplemented.InordertoconfigureLPSforaspecificproject,thefollowingquestionsmustbeanswered:RelationshipoftheLastPlannerSystemtootherProjectManagementComponents● IstheLastPlannerSystemdefinedandunderstoodassomething

distinctivelydifferentthanProjectControls?● WhatisitsinteractionwithProjectControl,especiallywithhigherlevel

schedules?● Whatisthescope(allphasesorjustconstruction)ofLPSimplementation?● Whatrolewillphysicalcontrols,sensorsandautomatedequipmentplayin

controllingwork,resolvingconstraintsandensuringqualityofwork?ConfigurationoftheLastPlannerSystem● Whohaswhatrolesandresponsibilities?● HowwillthePhasesbedefined?● Howmanyweeksaheadofscheduledstartwilleachphasebeplanned?● Howlongwillthelookaheadschedulebe?Note:Thismayvarybyphase,

dependingontheleadtimerequiredtoremoveconstraints.● Howfarinadvanceofcommitmentplanningwillthetasksbebrokendown

toappropriatelevel?e.g.,3weeksaheadofscheduledstart,2weeksaheadofscheduledstart.

● Howlongistheplanninghorizonforcommitmentplanning;oneshift,½day,1day,1week,etc.?

● Whatwillbetheweekly,monthlycycleofLPSevents?● Whatarethestandardagendasandparticipantsforphaseplanning,

lookaheadplanningandcommitmentplanningmeetings?● Whatplanfailureswillbeanalyzedinsearchofcountermeasures?Who/how

willthedecisiontoanalyzebemade?Howwillanalyzesbecarriedout?Implementation● Howwilltheworkofprojectteammembersoffsitebeincorporatedintothe

LastPlannersystem?● Willtheimplementationbedonetopdownorbottomup?● Howwilleducation&trainingbedone?● Howwilltheeffectivenessofimplementationbeassessedandimproved?


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I.FutureResearchWedonotbelievethatthecurrentbenchmarkisthebestthatcanbeachieved,especiallyasregardsmethods.Indeed,giventheleanprincipleofcontinuousimprovement,betterpracticeisalwayspossible.Basedonresearchtodate,weofferthefollowingtaskstobeperformedandhypothesestobeexploredandexperimentallytested:

1. DevelopandtestpotentialhighleveragedriversofLPSperformance.Thecriticalquestiontobeansweredis“Whatarethefewactionsorbehaviorsoftheprojectteam,whileworkingintheprocess,thatarehighlycorrelatedwithdesiredprojectoutcomes?”Thenextstepthenwouldbetodevelopmetricstomeasurethesedesiredactionsandbehaviors.Somepreliminarythoughtsinthisarea,whicharebasedonfieldexperiencewithsuccessfulandunsuccessfulLPSimplementations,arecenteredontheteam’sabilitytomaketherighttaskssoundintherightsequenceandrate.Itappearsthatthekeyfactorsinvolvedaretoadequatelyidentifyandremoveconstraintsinadvanceofscheduledworkandtolearnfromplanfailures.TeamsthatdowellwiththistendtohavehighPPCandaremeetingorexceedingscheduleandbudgettargets.Thecrucialunderlyingabilitiesseemtobe(1)havingstablelookaheadschedules,(2)requestingandobtainingreliablecommitmentstoremoveconstraints,and(3)developingandimplementingcountermeasurestopreventrepeatedplanfailures.ThehypothesistobetestedwouldbethatfocusingontheimprovementofthesethreeabilitieswillresultinimprovedPPCandbetterattainmentofintermediatescheduleandbudgettargets.Tohelpfocusteamsonimprovingthesefundamentalabilities,indicatorsareneeded.TheexistingTasksAnticipatedmetric(TA)measuringthechangesineachweekofthelookaheadwindowmayserveasanadequateindicatorinregardsto(1).For(2),perhapsmeasuringeachweek“PercentPromisesMade”(numberofreliablecommitmentstoremoveunresolvedconstraints/totalnumberofunresolvedconstraints),“PercentPromisesKept”(Numberofconstraintsresolvedintheweekaspromised/Totalnumberofconstraintspromisedtoberesolvedintheweek)willfocustheteamonthedesiredbehaviors.For(3),apotentialmetricmightbeameasureofthenumberofcountermeasuresimplementedrelativetothenumberofplanfailuresoversomepasttimewindow.CourtesyofJohnDraper,LeanProjectConsulting

2. Developmeanstoassessthequalitiesofphaseplans.Whenateamengagesinphaseplanning,participantsexploreoptionsforhowworkcanbestructuredandtheydefinehand-offsbetweentheirso-


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definedchunksofwork.Thatplanningprocessalltoooftenendswhenonefeasibleplanhasbeenidentified.

Iftheteamfindsoneplanthatisfeasible,mighttheybeabletofindadditionalonesthatarefeasibleaswell?Ifso,mightsomeoftheseplansbebetterthanothers?Weneedmetricstoassessthequalitiesofphaseplanssowecandiscriminatebetweenthemandchoosetheonemostsuitabletodelivertheprojectathand.

Metricsmaypertaintothedegreeofflowthathasbeenachieved,forexamplebygaugingtheextenttowhichtradecrewswillbeabletoworkwithoutinterruptions(e.g.,don’thavetoleavethesiteandduetolackofworkreturnonlyseveraldayslater).Inourongoingresearchontakttimeplanningwearedevelopingothermetricssothatwecangaugehowwellaplanmeetsthefollowingobjectives:Havetradesworkinawaytheyprefer

• Aimforconstantcrewsizesandcontinuousworkflow• Avoidtradestacking• UsetimelyonTakthandoffs• Balancethewholewhilepushingforspeed

3. DevelopmorestandardworkWorkthatrollsover(itpassesthescreeningprocess)fromthephaseplanintothelookaheadschedule,willthenbemadereadyoverthecourseofthedurationofthelookaheadtimewindow.Workchunks(“boulders”)getbrokendowntosmalleronesintheprocess(to“dust”)untiltheyareofasizeaLastPlannercancommittowhenmakingtheirweeklyworkplan.Atpresent,wearenotawareoftheirbeingastandardmethodologyforconductingthisbreakdownnorofastandardworkdescriptionthatresultsfromit.Somestandardizationisbeingdone,forexample,aworkstandardgetsestablishedafteraFirstRunStudy.Developingmoresuchstandards,anddoingsoconsistently,willhelpwithlearningonhowworkcanbedonewithinandacrossprojects.

3. Howdocurrentpoliciesandpractices,includingcommercialcontracts,obstructsuccessfulLPSimplementation?

4. Extendreliablepromisingtodirectworkers.Thishaspreviouslybeenrecommendedfordesign,wheremoreworkisdonebyindividualspecialiststhaninconstruction,sotheabilitytoassesscapacitywhenrespondingtorequestscallsforindividualworkplansatthecommitmentlevel.AprocessforsolicitingandgettingcommitmentsfromindividualconstructionworkersisnowinusebyVeidekkeandSkanskainNorway.Theresearchcouldstartbyexaminingcurrentpractices,assessingtheirimpact,andexperimentingwithrefinementsasneeded.Howtoovercomeobstaclestoextendingreliablepromisingtodirectworkers,suchasfrequentchangeindirectworkersonprojects,couldbeincludedintheresearch.


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5. Resourceloadcommitmentplans;i.e.,planstocompleteandreleasework

nextweek,nextday,nextshift.Commitmentsshouldbemadewithinavailablecapacityandallcapacityshouldbecommitted,mindfulofunderloadingtoassurereliableworkflow.[Thisisbeingdonealready,butisnotauniversalpractice.]

6. Increaseuseofvisualstocommunicateinformation.Forexample,leadingindicatorsthatprovideinformationwhatneedstobedonenowtomovetheprojecttowarditsobjectives.

7. BenefitsandchallengesofLPSsoftwaresolutions.Thisresearchwouldbeginbyspecifyingthecriteriaforevaluation;generally,dotheyhelppromotethepracticesadvocatedinthisLPSBenchmark,andinwhatconditionsaretheymosteffectiveorneeded.

8. RelationshipsbetweenLPSandsafety,quality,costandtimeperformance.“DoesLPS,properlyimplemented,reduceillnessandinjuryonconstructionsites?Doesitreducedefects,reducecost,andreducetime?”Thereissomeevidenceregardingimpactonsafety(MTH,aDanishcontractor,reporteda75%reductioninlosttimeaccidentsonprojectsusingLPS),quality(ontheTemeculaValleyHospitalProject,1of1300inspectionsfailedfirsttime),andcost(Liuetal.’s2009paperreportingapositivecorrelationbetweenLPSandlaborproductivity;Gonzalezetal.’s2008paper),andprojectdurations(BoldtConstruction’sworldrecordonaStoraEnsoproject).Butmoredataisneeded.WiththebroadertakeupofLPS,statisticalanalysisshouldnowbepossiblewithlargerdatasets.

9. LPSisdesignedtobeanengineforcontinuousimprovement,themechanismofwhichisshrinkingbuffersbyreducingvariation.Towhatextentisthatpotentialbeingexploitedintheindustry?

a. Hasanyonereducedcapacitybuffersinresponsetoconsistentlyachievingnear-100%PPC?

b. Hasanyonereducedtheirschedule(time)buffersinresponsetoconsistentlyhittingphasemilestones?

10. Conversationsforaction(reliablepromising)playacentralroleinLPSascurrentlydesigned,butlanguageactionalsoincludesconversationsforpossibility.HowmightconversationsforpossibilitybeincorporatedintoLPS?Whatbenefitsarerealizedfromthatincorporation?

11. Giventheincreasinguseofrelationalcontractsthatinvolvedesignersandconstructorsintheearlystagesofprojects,collaborativegenerationofprojectmasterschedulesisanappropriateresearchtopic--howtodoit,whomtoinvolve,criticalpreconditions,etc.Andonprojectswheretheparticipantsshareriskandreward,thesearchforbetterphaseplans,plansthatoptimizeworkflow,isclearlyappropriate--beyondsimplysqueezingtheworkwithintheavailabletime.

12. ExtensionofmanagerialresponsibilitytofrontlinesupervisorswasoneofthemotivationsforthecreationofLPS.However,thatdoesnotmeanthereis


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noroleforotherlevelsofsupervision.MoreexplicitspecificationofthoserolesandresponsibilitiescouldbehelpfulingettingLPStofunctionproperly,andtofacilitateitsuseincontinuousimprovementthroughsystematically‘loweringtherivertorevealtherocks’.

13. Planningandcontrolisfocusedondeliveryofwhat’sneededbyclientstoaccomplishtheirpurposes,andtheirconditionsofsatisfaction(forcosttime,etc.).Intheconstructionphase,itmaybeassumedthatdeliveryofvaluetocustomersisaccomplishedbybuildingtothedesigndocuments.Consequently,decidingwhatworkistobedoneinwhatsequenceisachievedintheconstructionphasebyconsiderationofprojectcostandscheduleobjectives--what’sthebestwaytomovetowardthoseobjectivesfromwherewearenowandwithwhatwenowhaveinhand.Whendesigningtheasset,thatobviouslycannotbeassumed.Whatisdonenow,withvariousdegreesofsuccess,issynchronizingdrawingdeliverydateswithconstruction’sexecutiontimes,butthat’sdonelateinthedesignprocess.Howaresequencingdecisionsbestmadeinearlydesignbeforeproductionofconstructiondocuments?

14. Severalmethodsfromsoftwaredevelopmentarenowbeingusedinplanningandcontrollingdesignworkintheconstructionindustry;e.g.,ScrumandDavidAnderson’sKanban.AdescriptionandevaluationofthesemethodsshouldbedonetodecideiftoincorporateintofutureLPSBenchmarks.

15. Whenacommittedtaskcannotbecompleted,askthedirectworkersinvolvedtoexplainwhathappened;totakethefirststepsina5Whysanalysis.Prearrangewhohasresponsibilityforcontinuingtheanalysisdependingonthecategoryofreasonforplanfailure.

16. Explorehowtobetterproduceproactiveprojectexecutionstrategiesandmilestoneplans,thatmakeuseofestablishedknowledgeaboutplanningunderuncertaintyonwhereandwhentodevelopflexibilityandbuffers,andtheproperrelationshipofthosestrategiesandprojectcontrolschedules.CourtesyofHajnalkaVaagen,NTNU

17. Howdoes Last Plannerwork to enable resilience in projects,what are thesocial-behavioural prerequisites for successful Last Plannerimplementations, and does/how does Last Planner strengthen socialnetworksandthusincreaseresilience?Courtesy of Hajnalka Vaagen, NTNU

18. Everydayimprovement:whatcanbedonetoimprovethewayprojectteamsandtradeteamslearnandimproveonadailyandweeklybasiswiththeLastPlannerSystem?CourtesyofAlanMossman,TheChangeBusiness

19. LPScaninfluenceavarietyofsocialdynamicswithinaconstructionorganisationSocialdynamicsreferstotheresultingbehaviourofgroupsfromtheinteractionsofitsindividualmembersandtheanalysisoftheconnectionsbetweenindividualinteractionsandgrouplevelbehaviours(DurlaufandYoung,2001).Atthispoint,trusthasbeenoneofthemorerelevantsocialdynamicvariablesstudiedtodate.ButtheLPScanendanger


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synergiesandfeedbackloopswithothersocialdynamicsvariablessuchasPowerDistanceandGoalSetting.Thisresearchcouldstartapplyingavarietyofsocialsciencetechniquestoexplorethefollowingquestions:whatspecificsocialdynamicsvariablesandmechanismsareendangeredbyLPSinaconstructionorganisation?andhowdotheyinteract(synergiesandfeedbackloops)?.ThequestionsestablishedinanexploratoryphasedcanbefurtherstudiedbyusingcomputermodellingtechniquessuchasAgent-BasedModellingorSystemDynamics.EmpiricaldataandexperimentalsettingscandemonstratethatLPSsocialresearchgobeyondthattraditionalfocusonlanguage-action-perspective,peopledevelopment,cultureandtransformation,andintegraltheory,andpayattentiontospecificsocialdynamicsvariables(otherthantrust)thatcanpromoteamoreeffectiveadoptionoflean-basedtoolssuchasLPSinaconstructionorganisation.

Durlauf,S.andYoung,H.P.,2001.Thenewsocialeconomics,Cambridge,MA,USA:MIT.González,V.A.,Sacks,R.,Pavez,I.,Poshdar,M.,Priven,V.andBenAlon,L.(2015).InterplayofLeanThinkingandSocialDynamicsinConstruction.Proceedings23rdInternationalConferenceforLeanConstruction,Perth,WesternAustralia,28th–31stJuly.CourtesyofVicenteGonzalez,Univ.ofAuckland

J.FrequentlyAskedQuestionsA. WhyshouldLPSbeconsideredaleanmethod?Answer:Leanisaphilosophy

ofmanagementdedicatedtoincreasingvaluedeliveredtocustomersandstakeholders,andtodecreasingwaste.Valueisincreasedwhenprojectsdeliverwhatcustomersneedtoaccomplishtheirpurposes,withincustomerconstraints(oftime,cost,location,codes,etc.),andwhenwhat’sdeliveredenablesexpansionofcustomerpurpose.LPSisamethodfordecidinghowtoachievetheseobjectives,andforsteeringprojectstowardthem.IntheToyotaProductionSystem,threetypesofwasteareidentified:muri,muraandmuda.Muriisoverloading,muraisunevenness,andmudaiswhatisunnecessary.Allaretobeavoidedtotheextentpossibleataspecifictimeandplace.LPSaddressesallthree.Overloadingisavoidedwhentasksaredesignedtothecapabilitiesoftheresourcesassignedtotheirexecution.Unevennessisavoidedwhenthereleaseofworkismademorepredictable.Whatisunnecessaryisavoidedwhentasksareexecutedinasequencethatreduces/eliminatesrework,andalsowhenresourceutilizationisincreased.

B. WhatistherighttargetforPPC?Answer:100%.Thegoalisreliablereleaseofwork,soanythinglessthanaPPCof100%isafailuretofullyachievethatgoal.Somepeoplethinkthata100%goalencouragessandbagging,butthat’s


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trueofanygoal,andtheonlyeffectivecountermeasureispersuadingprojectteammembersthatPPCmeasurestheeffectivenessoftheplanningsystem;thoughsupervisoryoversightcanalsohelp.Don’tconfusea100%PPCgoalwithoverloadingresources;i.e.,notallowinganycapacitybufferforvariationinprocessdurations.Wealwayswanttounderloadwhenmakingassignments,butwiththegoalofperfectworkflowreliability.Ascountermeasuresaredevelopedforplanfailures,actualcapacitywillincrease.AsPPCapproaches100%,increasetheloadplacedoncapacityandreducethetimeslotsinplanning;i.e.,plantothe½dayratherthantheday.

C. Howmuchshouldcapacitybeunderloaded?Answer:Giventheimportanceofworkflowreliability,wherefeasible,weshouldunderloadsothatthereisa99%chancethattheassignedcapacitywillbesufficienttocompletethetaskasscheduled.Buttodothatpreciselyrequiresinformationconcerningthestandarddeviationfortherelevantoperations.2standarddeviationscorrespondstoa95%confidencelevel.3standarddeviationscorrespondstoa99%confidencelevel--meaningthattheunderloading(capacitybuffer)willbesufficient99timesin100inachievingtargetcompletiondates.Thisshowshowvaluableitistoreducethestandarddeviation!Inpractice,thestandarddeviationmaynotbeknown,inwhichcase,welearnfromourexperienceandmakeadjustmentsaccordingly.

Anotherrelevantpointhereisthatwetendtowastesomethingontheorderof30%ormoreoflaborcapacitywhenworkflowreliabilityislow.Thatcanbeconsideredabuilt-inbufferforunderloading.Underloadingimpliessomelossoflaborcapacity,butthatlosswillbelessthanwhathashappenedhistoricallybecauseunderloadinghelpsimproveworkflowreliability.

D. Howmanyweeksshouldwelookaheadwhendoingconstraintsanalysis?Answer:Thatnumberofweeksrequiredtoremovetheconstraintwiththelongestleadtime.Example:Aconstructiontaskfirstentersthelookaheadwindow.Iftheneededdesigninformationisbehindschedule,a6weeklookaheadprovides6weekstoexpediteproductionanddeliveryofthatinformation.Ifthedesignresourcesarenotdedicatedorotherwisehaveuncertaincapacity,moreweeksmaybeneeded.Notethatconstraintssuchasdesigninformationandmaterialshavealreadybeensynchronizedwiththeconstructionschedulebecausetheyhaveleadtimesfarexceeding6weeks.Therelevantleadtimehereisforsolvingproblemswithdesigninformation,materialsandsuch.Itemswithleadtimesforproductionanddeliveryexceedingthelookaheadwindowaretobeembeddedinhigherlevelschedules.

E. Howtoselectwhichplanfailurestoanalyzeinsearchofcountermeasures?Answer:Asmanyasyouhavecapacitytoanalyze.Assuminglimitedcapacity,selectthosewiththebiggestimpactonprojectperformance.


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F. HowisPPCmeasured?Answer:Attheendofthecommitmentplanperiod

(1shift,1week,1day,etc.),theteamnoteswhichcommitmentshavebeenmetandwhichhavenot.Acommitmentisunderstoodtohavebeenmetwhenitwasdoneasplannede.g.,startedand/orfinishedasplanned.Thisisusuallydonebyaskingthequestion“Didwedowhatwesaidweweregoingtodo?”i.e.“Didwestartthetaskasplanned?”“Didwefinishitasplanned?”Theappropriateresponseiseither“Yes”or“No.”Thereisnopartialcredit.ItisimportanttorealizethatPPCisameasureofateam’sabilitytoreliablyplanandexecuteworkandisNOTameasurementofcompletedwork.NorisPPCameasureofproductivity.Itispossibletohave100%PPCandpoorproductivityifcapacityexceedsreadywork.Therecommendedplanningprecisionistoplantothedayorshift(althoughafterachievingnear100%PPC,thatcanchangetothe½day,etc.).Countingtasksfinishedbytheendofaweekinvolvescommittingonlytotasksthatarefullysoundatthebeginningoftheweek.Thelargerthebatchsizeofcommitments,thelongertheprojectwilltaketocomplete.

G. Shouldearlyfinishesbecountedascompletions?Answer:Yes,iftasksarecompletedwithinthecommittedtimeframe,theyshouldbecountedascompletions.Toincreasetheprobabilitythatcommittedtaskswillbecompletedontime,weadviseunderloading;i.e.,assigningmorecapacity(laborhours)thanmightbeneeded,allowingforvariationinprocessingdurations.Completingearlyisexpectedanddesired.Whatwewanttofocusattentiononisexcessivelyearlycompletions.Thatcanbedonebytaggingtaskscompletedearlyanddiscussinginthedailyorweeklyplanningmeetingsifthereisanopportunityforadjustingfuturetaskdurationsorcapacityallocation.Thatisthejobofthemanageroftheplanningmeetingsandthelastplanner’simmediatesupervisor.Toavoidlossofcapacity,itisadvisedtoincludeincommitmentplansbothprioritytasksandothersavailableasfollow-onorfallback.Takecarenottousecapacitytoperformtasksthatareotherwiseready,butdoingnowcausesmorepainlaterintheproject--forexample,usingtemporaryhangers(#9wire)toputpipespoolsintotheirfinalpositioninordertoclaimmoreprogressandhencepayment.Whenthepipesupportsarrive,theywillbemoredifficulttoinstallthanwasexpectedinbudgeting.Anotherpossibleuseforexcesscapacityistohaveworkersparticipateinproblemsolving;e.g.,5whysanalysisofplanfailuresorrevisionsofoperationdesignsthathavebeenshowntoneedimprovement.

H. IsLPSaschedulingsystem?Doesitreplaceprojectcontrols?Answer:No,LPSisaproductioncontrolsystemwithelementsofplanning,schedulingandexecution.Adistinctionshouldbemadebetweenplanningandscheduling–planningistheupfrontactivityofdeterminingwhatshouldbedone,inwhatsequence,howitshouldbedone,andlininguptheresourcestodothework.Theplanbecomesaschedulewhencommitmentsaremadetoaccomplish


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certainworkoncertaindays.LPSfunctionsinthedimensionsofplanning,scheduling,executionofwork,andlearningfromplanning/executionvariances.LPSdoesnotreplaceprojectcontrols,thefunctionofwhichistheestablishmentofcost,timeandotherperformancetargets(See“WhyLastPlanner?”atthebeginningofthisdocument).LPSisthenusedtosteerprojectperformancetowardstheobjectivessetbytheprojectcontrols.

I. HowmanymoremeetingsandemployeeswillweneedifwedoLPS?Answer:None.Infact,youmaybeabletoreduceindirectsasworkflowreliabilityincreases,reducingtheamountoffirefighting.

J. Shouldwehavecrewsdomoreworkiftheycompletecommittedtaskssoonerthananticipated?Answer:Yes,butonlyifthatworkdoesnotcausemoreharmdownstreamthanthebenefitprovidedbyusingotherwiselostcapacity.What’sneededistospecifyoncommitmentplansPlanBtasksavailableforeachworkgroupshouldtheycompletecommittedtasksearlyorshouldtheybeunabletoperformcommittedtasks.

K. Whythename“LastPlanner”?Answer:Thenamedesignatesthefrontlinesupervisorswhoseplansinitiateproductionasopposedtofeedinglowerlevelsofplanning.“LastPlanner”wasusedbecausethepositionthatfunctionsasfrontlinesupervisorcanvaryfromplacetoplace,andthenamesforthosepositionsalsovary.Forexample,“capataz”inSouthAmericacorrespondsroughlyto“foreman”inNorthAmerica,butinmanySouthAmericanprojects,engineersactuallyfunctionaslastplanners.Thefrontlinesupervisorsofallcompaniesinvolvedindesignandconstructionareincludedaslastplanners,boththoseemployedbythecompanyleadingdesign(e.g.,anarchitecturalfirminabuildingproject)andconstruction(ageneralcontractor),andthefrontlinesupervisorsofengineeringconsultantsandofspecialtycontractors.Theexpression“LastPlanner”wasalsochosentoemphasizethatfrontlinesupervisorshavemanagerialresponsibilitiesandarenotsimplycogsinamachine.

L. DoesimplementationofLPStransferpoweroverprojectprogresstosubcontractors?Answer:No.Inatraditionalcontractingstructure,general(main)contractorshavefinancialinterestindeliveryofprojectsonoraheadofschedule,whilethefinancialinterestofsubcontractorsistousetheircrewsproductively.WhenLPSisusedonconstructionprojectswithsuchtraditionalcontractingstructures,thepartiesretaintheirdifferentinterests,butacttogethertoachieveboth.Generalcontractorscontrolprogressbyassuringthattasksaremadereadyintheneededsequenceandrateinlookaheadplanning,andbyreleasingtasksintoworkablebacklog.Theyhavemorecontroloverflowsofdesigninformation,materialsandequipmentthansubcontractors.Subcontractorscontrolproductivitybyparticipatinginlookaheadplanning,whichgivesthemforesightoffutureworkloadsotheycanmakebetterdecisionsaboutbringinglabortosite,bydesigningoperationsandbyincludingoncommitmentplansonlytasksthatarewell


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defined,sound,sequencedandsizedtothecapabilitiesofperformers.Iftheprojectscheduleiswellformed,andlookaheadplanningandcommitmentplanningdotheirjobs,bothprogressandproductivitywillbebetter.CourtesyofCarinaSchlabach,ZublinConstruction

M. Wholeadslookaheadplanning?Answer:Indesign,lookaheadplanningisusuallyledbythedesignprojectmanager.Inconstruction,lookaheadplanningisusuallyledbytheprojectgeneralsuperintendent.Onlargerprojects,lookaheadplanningmaybedividedbetweenareasorsystems,inwhichcasethedesignmanagerorsuperintendentovertheareaorsystemprovidesleadership.

N. Wholeadscommitmentplanning?Answer:Sameleadersasforlookaheadplanning.WhenLPSisworkingwell,thelastweekofthelookaheadisthedefaultcommitmentplanforthefollowingweek,andcommitmentplanningmeetingsaredevotedtomakinganyneededchanges,andtodecidingaboutPlanB(fallback/follow-ontasks‘belowtheline’).

K. AcknowledgementsAlthoughresponsibilityforerrorsandomissionsinthisdocumentisP2SL’sresponsibilityalone,thisLPSBenchmarkwasproducedthroughthecombinedeffortsofmanypeople.JasonKlousandJohnDraper,bothofLeanProjectConsulting,JamesChoofromStrategicProjectSolutions,andMikeWilliamsoftheProjectProductionInstitutelaboredmightilyonthedraftofthedocumentthatwassentforcommenttoexternalreviewers.ValuableinputwasreceivedfromexternalreviewersTariqAbdelhamid,MichiganStateUniversity;DickBayer,theRealignmentGroup;SamirEmdanat,GhafariAssociates;VicenteGonzalez,UniversityofAuckland;OleJonnyKlakegg,WSP;LauriKoskela,UniversityofHuddersfield;AlanMossman,TheChangeBusiness;CarinaSchlabach,ZublinConstruction;BillSeed,TransformationAchieverCoach;SteveWard,6ixConsulting;DavidUmstot,theRealignmentGroup;andHajnalkaVaagen,NorwegianUniversityofScienceandTechnology(NTNU).Andnotleast,agrantfromtheProjectProductionInstituteisgratefullyacknowledged.

L. GlossaryActivityDefinitionModel(ADM):

Aninput-process-outputrepresentationofworktobedoneindesignorconstruction.Themodeldepictsthespecificationofdirectives(enteringtheprocessrectanglefromabove),prerequisites(includingmaterialsandinformationtobetransformedintothedesiredoutput,enteringtheprocessrectanglefromtheleft),andresources(enteringtheprocessrectanglefrombelow).Italsoshowsaninspectionprocessresultingeitherinredoorreleasetothecustomerprocess.The


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modelisusedasaguidetoexplodingscheduledtasksintoalevelofdetailatwhichtheirreadinessforexecutioncanbeassessedandadvanced.

Figure5:ActivityDefinitionModel

Breakdown:Deviationfromtargetoutcome(s).Planfailures,errorsanddefects,andoccupationalillnessesandinjuriesarecommonbreakdownsinconstruction.

Buffer:Amechanismfordeadeningtheforceofaconcussion;e.g.,acapacitybufferiscreatedbyschedulinglessthanallthetimeavailable(aka.underloading).Ifproductionfallsbehindschedule,thereiscapacityavailableforcatchingup.Capacitybuffersmaybepreferredoverinventorybuffers.Inadditiontocapacityandinventorybuffers,othertypesofbuffersaretimebuffers,monetarybuffers(contingency),andspatialbuffers(tolerances).Arguably,monetarybufferscanbeconvertedinto,e.g.,capacitybuffersorinventorybuffers.CommitmentPlanning:Nearterm(day,shift,week)plansthatconsistoftasksthathavebeenscreenedfordefinition,sequence,soundnessandsize,andhavebeennegotiatedbetweenimmediaterequesterandperformerusingreliablepromising.ConditionsofSatisfaction:Conditionsthatarequestorplacesonperformanceofapromise;e.g.,whenitistobecompleted,howmuchtherequestorwillbeaskedtopay,etc.

Commitment:Apromisemadebetweena‘supplier’anda‘customer’toperformanagreedtaskbyacertaindate.Commitmentsaremadetothedayorshift,dependingonthenatureoftheproject.Aswelearnhowtobereliableplanningtotheday,wecanbeginlearninghowtobereliableplanningtothehalfday,andsoon.

Constraint:Somethingthatstandsinthewayofataskbeingexecutableorsound.Typicalconstraintsondesigntasksareinputsfromothers,clarityofrequirementscriteriaforwhatistobeproducedorprovided,approvalsorreleases,andlaboror


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equipmentresources.Typicalconstraintsonconstructiontasksarethecompletionofdesignorprerequisitework;availabilityofmaterials,information,anddirectives.Screeningtasksforreadinessisassessingthestatusoftheirconstraints.Removingconstraintsismakingatasksound.

Dailyhuddles:Brief,typicallystand-up,meetingseachdaybygroupsofinterdependentplayers,atwhicheach,inturn,shareswhatcommitmentstheyhavecompleted,whatcommitmentstheyneedhelpwithorcannotdeliver.Thiscanbedonewithinadesignsquadorconstructioncrew,andbetweenfrontlinesupervisorsofdesignsquadsorconstructioncrews.DCAP(Detect-Correct-Analyze-Prevent):Aprocessforreactingtoandlearningfrombreakdowns.Detectbreakdownsasclosetothesourceaspossible.Takecorrectiveactionsotheoperationcanberestarted.Forexample,correcterrorsondrawingsandreplacepreviousdrawingswithcorrected.Analyzethebreakdowntofindcountermeasures.ImplementthecountermeasurestoPreventreoccurrenceofthebreakdown.

Firstrunstudies(FRS):Firsttrialexecutionofanoperationasatestofcapabilitytomeetsafety,quality,timeandcosttargets.TheFRSbeginsseveral(e.g.,2or3)weeksaheadofthefirstrunwithaplanningsessioninwhichtheteamthatwilldothatworkisinvolvedindevelopingadetailedworkplanatthe‘step’leveloftaskbreakdown,soeachpersonontheteamknowswhattheyaretodo.Firstrunstudiesfollowtheplan-do-check-actcycle.Theplanisdeveloped,thefirstruniscarriedout,theresultsarecheckedagainstthetargets.Iftheresultsareinadequate,theoperationdesignisreplannedandthetestperformedagain.Thiscontinuesuntiltheoperationisconsideredcapable,thenthatwayofdoingthattypeofworkisdeclaredthestandardtomeetorbeat.First-runstudiesaredoneaheadofthescheduledfirststartoftheoperation,whilethereistimetoacquiredifferentoradditionalprerequisitesandresources.Firstrunstudiesareoneofthreewaysinwhichoperationscanbedesigned:theothertwoarevirtualprototyping(virtualfirstrunstudiesorVFRS)andphysicalprototyping(mockups).

FiveWhys:Askingwhyrepeatedlytohelpuncovercountermeasurestoreoccurrenceofaproblem.Usuallythe‘rootcause’isidentifiedwithin5“whys”.

Frequencyofplanfailures:Thepercentageoftotalplanfailuresfromeachprimarycategory;e.g.,lackofprerequisitework,lackofdesigninformation(noneordefective),lackofmaterials,changedpriorities,orfailureinexecution.

Lookaheadplanning:Thelevelofplanningbetweenphaseschedulesanddaily/weeklyworkplans,dedicatedtomakingscheduledtaskseligibleforcommitment.Thatisdonethroughconstraintsanalysisandremoval,breakingdowntasksintooperations,andcollaborativelydesigningthoseoperations.Whenconstraintscannotberemovedoncriticaltasks,replanningisinitiated.


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Masterschedule:Schedulecoveringanentireprojectstart-to-finish,thenfurtherdetailedandvalidatedinphasescheduling,theactivitiesinwhicharethenexplodedwhencreatingthemake-readyschedule.Milestone:Completionpointofprojectphasessuchassubstructure,superstructure,utilityrough-ins,andfinishesonabuildingproject.

PDCA(Plan-Do-Check-Act):Processforlearningfromexperiments.Experimentsstartwithahypothesisabouttheconsequencesofanaction,formulatedinaPlan.Forexample,itmightbehypothesizedthatimprovingworkflowreliabilityincreasesproductivity.Doisperformingtheexperiment;i.e.,takingtheaction.Checkisassessingtheconsequencesoftheaction,inthiscasemeasuringifproductivityincreaseswithbetterworkflowreliability.Afterappropriaterevisionsandretests,Actconsistsinstandardizingpractice.TheAnalyzestepinDCAPisthePDCAprocess,inwhichthehypothesistobetestedisthecountermeasureproposedtopreventthebreakdownbeinganalyzed.PercentPlanComplete:MetricusedintheLPStogaugeplanreliability.Thepercentageofactualcompletionstoplannedcompletionsinadailyorweeklyworkplan.PhaseScheduling(alsocalledReversePhaseScheduling):OnelevelinLPS,whereaphasegetsbrokenoutfromthemasterplan,inwhichmilestonesdefinephases,andpeopleresponsiblefortheworkinthatphasejointlydeveloptheplan.Peopleina“designphase”mayincludeengineers,architects,owners,designers;perhapsalsoconstructorsandpermittingagents.Peopleina“constructionphase”mayincludedesigners,thegeneralcontractorandspecialtycontractors,perhapsalsoowners,inspectorsandcommissioningagents.Pullplanningisusedtoidentify,defineandsequencetasks,creatingalogicnetwork.Thephasescheduleisproducedbyassigningdurationstotasksandarrangingthemonacalendar.

Physicalprototyping:Testingaproductorprocessdesignusingmock-ups.Productioncontrol:Steeringtowardprojectsafety,quality,timeandcosttargets

Projectcontrols:Settingprojecttimeandcosttargetsandtrackingprogresstowardthem.Pullplanning:Amethodofplanningcollaborativelywiththosewhoaretodotheworkbeingplanned.Featuresincludefirstdoingabackwardpassfromthetargetcompletiondateortimeoftheworkbeingplannedandcreatingaschedulebufferthatisallocatedtocriticalandriskytasksintheplan.Theinitialoutputisalogicnetworkshowingthetemporaldependenceoftaskstobeperformedinthephase,process,oroperationbeingplanned.Aschedulecanbeproducedbyestimatingtaskdurations.


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Reliablepromising:PromisereachedbystickingtothestepsoftheLanguage-Actioncycle(aka,WorkflowLoop):(1)Makingarequest,(2)Negotiating(clarifications,conditionsofsatisfaction,andcounteroffers),(3)Committing,(4)Executing,(5)DeclaringComplete,and(6)DeclaringSatisfaction.

Resources:Labororinstrumentsoflabor,includingtools,equipment,andspace.Resourceshaveproductioncapacitiesaswellascosts.Consequently,materialsandinformationarenotresources,butratherwhatresourcesactonorprocess.Taskbreakdown:Thetasksinvolvedinexecutingaprojectcanbeusefullydescribedatdifferentlevelsofdetail,butthereisnogenerallyacceptedstandard.Weproposethefollowing:projectsarecomposedofphases,phasesarecomposedofprocesses,processesarecomposedofoperations,operationsarecomposedofsteps,andstepsarecomposedofelementalmotions.Anexample:Calhoun101Projectconsistsofphases,includingtheSubstructurephase.TheSubstructurephaseconsistsofprocesses,includingPlaceDrilledCaissons.TheprocessforPlaceDrilledCaissonsincludestheoperationFabricateCage.FabricateCageconsistsofstepsincludingFitandTackLiftingBands,whichcouldbe(butrarelyis)furtheranalyzedintoelementalmotionssuchasgrasp,lift,rotate,etc.—howarobotwouldbeprogrammedtodothattask.Taskdefinition:Arequirementforinclusionondailyorweeklyworkplansisthattasksaredefinedsothatperformersunderstandwhatistobedone,where,when,bywhom;candeterminewhatisneededbywayofmaterials,information,tools,andequipmenttoperformthetask;andtaskcompletioncanbeeasilyassessed.Tasksequence:Theorderintimeofasetoftasks.Arequirementforinclusionondailyorweeklyworkplansisthattaskscanbeperformednowwithoutincurringapenaltylater.

Tasksize:Arequirementforinclusionondailyorweeklyworkplansisthattasksaresizedtothecapabilityofthosewhoaretoperformthemwithinthetimeconstraintsoftheplan.Thisimprovesworkflowreliability.Asperformersincreasetheircapability,moreworkisassignedtothem.Tasksoundness:Arequirementforinclusionondailyorweeklyworkplansisthatingeneraltaskshavehadallconstraintsremovedpriortostartofexecution.Notehoweverbyexceptionreasonablebetscanbemade;forexample,regardingthereliabilityofsuppliersdeliveringmaterialsneededintimetoperformthetask.

Tasksanticipated(TA):AmetricintheLPSthatmeasuresthepercentageoftasksforatargetweekinthelookaheadthatwereanticipatedinanearlierplanforthattargetweek.Theobjectiveofthisindicatoristoprovidearelativemeasureofhowwelltheteamisabletopredictforthelookaheadtimehorizonwhatisactuallygoing


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tohappenontheproject.Thisplanningabilityiscriticalbecausewithoutit,someofthetasksthatneedtobedonecannotbemadeready.Inotherwords,TAmeasurestheinstanceswhentasksdropintotheWWPthatwerenotanticipatedatthebeginningofourlookaheadplanningwindow.

Tasksmadeready(TMR):TMRisametricinLPSthatgaugestheabilityoftheplan(ner)toforecast(predict)accuratelyinweekiwhattaskswilltakeplacej-iweeksintothefuture(TMRij).Itgaugesthepercentageoftasksinanearlierplanforatargetweekthatareincludedinalaterplanforthetargetweek.TogetherwithTAitcharacterizestheabilityoftheplanningteamtomakeworkready.

TAmeasureshowwellweareanticipatingwhattasksneedtobeexecutedwithinthelookaheadwindow,andconsequentlyisdrivenbytaskbreakdown.TMRmeasureshowwellweremoveconstraintsfromthosetaskssotheycanbeexecuted,andconsequentlyisdrivenbyconstraintsanalysisandremoval.Underloadingresources:Toallowforvariationthatcannotbereducedatamomentintime,resourcesareaskedtoproducelessthanwhattheycouldproduceiftherewerenovariationinarrivaltimesofinputsorinprocessingdurations.Thesecapacitybuffersaretobereducedasvariationisreduced;e.g.,byanalyzingbreakdownsandimplementingcountermeasures.Variation:Occurrenceofnon-uniformity.Forexample,processescanvaryintheirdurations,deliveriescanvaryintheirarrivalrelativetoduedate,productscanvaryintheirdefects,workloadcanvaryfromonedayorweektothenext,resourcescanvaryintheirrelationtoavailableworkload,etc.Reducingvariationisusuallypossible,buttherewillalwaysbesomeresidualvariationinproductionsystems.Asaresult,buffersoftime,cost,orcapacityareneededinordertoabsorbthatvariationandallowthesystemtofunction.

Variability:Thespreadinasetofdatapoints;measuredbyextentaboveandbelowamean,byvariance(theaverageofthesquareddifferencesfromthemean),andbystandarddeviation(thesquarerootofthevariance).

Virtualprototyping:Testingaproductorprocessdesignusingcomputermodeling.Visualcontrols&Visualdisplays16:Visualcontrolsareusedtomanageinputresources;e.g.,colorcodedhats,zoneplans,linessprayedonthefloor.Visualdisplaysareusedtocommunicateprocessstatus;publicallyplacedandeasy-to-interpretinformationregardingthestateofaprojectrelativetotarget(e.g.,71%complete,5%belowbudget,only1losttimeaccidentinthelast500,000laborhoursworked),theneedforhelpwithaproblem(e.g.,alightintheprojectofficethatflasheswhenworkersneedbricksdeliveredtothe7thfloor),thestatusofa

16DistinctioncourtesyofSteveWard,6ixConsulting.


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problem-solvingeffort—inshort,anythingthatgivespeopleontheprojectteaminformationtheyneed.

Workablebacklog:ThistermhasbeenusedintwowaysinLPS;1)tonametasksthathavebeenreleasedforcommitmentindailyandweeklycommitmentplans(seeFigure2inSectionF:Processes),and2)tasksthatareavailableasfallbackorfollow-onoptionsshouldspecialistsbeunabletocompletetasksoncommitmentplans,orcandomoretasksthanplanned,respectively.Werecommendusing“workablebacklog”inthefirstsense,torefertotasksthathavebeenreleasedforcommitment,and“PlanB”fortasksincludedoncommitmentplanstoserveasfallbackorfollow-onwork.

Figure6:FormingCommitmentPlans(courtesyofAlanMossman)

Alltasksoncommitmentplansaretobeselectedfromworkablebacklog,andtasksareplacedintoworkablebacklogonlyiftheysatisfycriteriafordefinition,soundness,sequenceandsize.Tasksthatarenotcritical,andhencearenotincludedinSHOULDonthelefthandsideofFig.6above,maybeplacedintoworkablebacklogiftheycanbeexecutednowwithoutincurringapenaltylater17.

CommitmentplansmayconsistofaPlanAandaPlanB.PlanAtasksarethosewhicharetrulyspeakingcommitments;othersaredependingonthembeingcompletedwithintheplanperiod.PlanBconsistsoffallback/follow-ontasksincasePlanAtaskscannotbecompleted,orasfollow-onworkincasePlanAtasksarecompletedearlierthanexpected.ItisimportantforallinterdependentplayerstounderstandbothPlanAandPlanB,toavoidconflictsoverspaceorothersharedresourcesandtomitigatesafetyhazardsfromworkinginnearbyspaces.Whenformingcommitmentplans,PlanAtasksareselectedfirstfromtasksthatSHOULDbedone(asshowninthemiddleofFig.6above).Ifthereisadditional

17Anexampleof‘alaterpenalty’:Inpursuitofmorereportableprogressandhencepayments,whenpipesupportsarelatearriving,pipespoolsmightbeerectedwith#9wire.Thisusuallyincreasesthedifficultyofinstallingthepipesupportswhentheyfinallyarriveandmustbethreadedthroughamazeofpipe,cabletray,conduit,andstructures.


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capacity,non-criticaltasksthatcanbeexecutedintheplanperiodwithoutincurringalaterpenalty(asshownintherighthandsideofFig.6above)canalsobeincludedinPlanA.Workflowreliability:AmetricinLPSmeasuredbyPercentPlanComplete(PPC).Itmeasurestheextenttowhichacurrentcommitmentplanaccuratelypredictsthestateoftheprojectatthestartofthenextplanperiod,andhencewhatworkloadwillbeavailableatthatpointintimeforthevariousspecialistsworkingontheproject.Ondifferenttypesofprojects,differentchoicesmaybemadeaboutthetimingofcommitments.Onmostconstructionprojects,therecommendationistoplantotheday,thoughoncedailyplansapproach100%,thetargetshouldchangetoplanningtothehalfday.Onverydetailedoperations,planningmaybetothehouroreventotheminute.

L.LastPlannerSystemPublicationsThefollowingarereferencesmadeinthispublicationplusaselectionfromthemanypaperspublishedontheLastPlannersystem.Ballard,Glenn(1997).“LookaheadPlanning.”5thAnnualConferenceoftheInternationalGroupforLeanConstruction,GriffithUniversity,GoldCoast,Australia.July,1997.Ballard,Glenn(1999).“ImprovingWorkFlowReliability”.Proceedingsofthe7thAnnualConferenceoftheInternationalGroupForLeanConstruction,Berkeley,California,July26-28,1999.pp.275-286.Ballard,Glenn(2000).TheLastPlannerSystemofProductionControl.PhDthesis,Dept.ofCivilEngineering,UniversityofBirmingham,Birmingham,U.K.,June,2000.Ballard,Glenn(2002).“Managingworkflowondesignprojects:acasestudy.”Engineering,ConstructionandArchitecturalManagement,9/3,June2002,pp284-291.Ballard,Glenn,JamieHammondandRomanoNickerson(2009).“ProductionControlPrinciples”.Proceedingsofthe17thannualconferenceoftheInternationalGroupforLeanConstruction,Taipei,Taiwan,July13-15,2009.

Ballard,GlennandGregoryHowell(1994).“ImplementingLeanConstruction:StabilizingWorkFlow.”Proceedingsofthe2ndAnnualMeetingoftheInternationalGroupforLeanConstruction,Santiago,Chile.(AvailableinLeanConstruction,A.A.BalkemaPublishers,Rotterdam,Netherlands,1997.)

Ballard,GlennandGregoryHowell(1994).“ImplementingLeanConstruction:ImprovingPerformanceBehindtheShield.”Proceedingsofthe2ndAnnualMeeting


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oftheInternationalGroupforLeanConstruction,Santiago,Chile.(AvailableinLeanConstruction,A.A.BalkemaPublishers,Rotterdam,Netherlands,1997.)

Ballard,GlennandGregoryHowell(1998).“ShieldingProduction:EssentialStepinProductionControl.”JournalofConstructionManagement&Engineering,ASCE,NewYork,NY,124(1)11-17.

Ballard,GlennandGregoryA.Howell(2003).“AnUpdateonLastPlanner”.Proceedingsofthe11thannualconferenceoftheInternationalGroupforLeanConstruction,Blacksburg,Virginia,August,2003.

Ballard,Glenn,GregoryHowell,andMichaelCasten(1996).“PARC:ACaseStudy.”Proceedingsofthe4thAnnualConferenceonLeanConstruction,Birmingham,England.(availableathttp://www.vtt.fi/rte/lean/)Ballard,G.,Tommelein,I.,Koskela,L.andHowell,G.(2002).LeanConstructionToolsandTechniques.Chapter15inBest&deValence(editors),DesignandConstruction:BuildinginValue.Butterworth-Heineman.Choo,HyunJeong,IrisD.Tommelein,GlennBallard,andToddZabelle(1999).“WorkPlan:Constraint-BasedDatabaseforWorkPackageScheduling.”J.ofConstr.Eng.andMgmt.,ASCE,125(3)151-160.Dekker,S.(2006).Thefieldguidetohumanerror.Bedford,UK:CranfieldUniversityPress.Deming,W.E.(1986).Outofthecrisis,MassachusettsInstituteofTechnology.Centerforadvancedengineeringstudy,Cambridge,MA,510.

Frandsen,A.G.andTommelein,I.T.(2016).“TaktTimePlanningofInteriorsonaPre-CastHospitalProject.”Proceedings,24thannualconferenceoftheInternationalGroupforLeanConstruction,Boston,143-152.González,V.,Alarcón,L.F.andMundaca,F.,2008.Investigatingtherelationshipbetweenplanningreliabilityandprojectperformance.ProductionPlanningandControl,19(5),pp.461-474.Hamzeh,F.,Ballard,G.andTommelein,I.,2012.Rethinkinglookaheadplanningtooptimizeconstructionworkflow.LeanConstructionJournal,1(1),pp.15-34.

Howell,GregoryandGlennBallard(1994)."LeanProductionTheory:MovingBeyond'Can-Do'."Proc.ConferenceonLeanConstruction,Santiago,Chile.September,1994.Howell,GregoryandGlennBallard(1994)."ImplementingLeanConstruction:ReducingInflowVariation."Proc.ConferenceonLeanConstruction,Santiago,Chile.September,1994.Howell,GregoryA.,GlennBallardandJeromeHall(2001).“CapacityUtilizationandWaitTime:aPrimerforConstruction.”Proceedingsofthe9thannualconferenceof


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theInternationalGroupforLeanConstruction,NationalUniversityofSingapore,August2001,pp.271-278.

Liu,Min,GlennBallard,andWilliamIbbs(2010).“WorkFlowVariationandItsRelationtoLabor--ACaseStudy”.JournalofManagementinEngineering,ASCE

Pound,Edward,Bell,JeffreyandSpearman,Mark(20140.FactoryPhysicsforManagers;McGraw-HillSeppanën,O.,Modrich,R.andBallardG.(2015).“IntegrationoftheLastPlannerSystemandtheLocation-BasedManagementSystem”.Proceedings,23rdannualconferenceoftheInternationalGroupforLeanConstruction,123-132.Tommelein,IrisD.andGlennBallard(1997).“CoordinatingSpecialists.”TechnicalReportNo.97-8,ConstructionEngineeringandManagementProgram,DepartmentofCivilandEnvironmentalEngineering,UniversityofCaliforniaatBerkeley.AlsoappearedinProc.SecondInt’l.SeminaronLeanConstruction,20-21October1997,SaoPaulo,Brazil,organizedbyA.S.I.Conte,LogicalSystems,SaoPaulo,Brazil.Tommelein,I.D.(1998).Pull-drivenschedulingforpipe-spoolinstallation:Simulationofleanconstructiontechnique.Journalofconstructionengineeringandmanagement,124(4),279-288.

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