How does the Last Planner System improve construction planning reliability?

Last Planner System (LPS) is lean construction planning method improving workflow reliability. Components: (1) Master schedule - milestone-level, (2) Phase pull planning - collaborative schedule working backward from milestones, (3) Lookahead planning - rolling 6-week window preparing work (make-ready), identifying constraints, (4) Weekly work planning - commitments from 'last planners' (foremen) who actually do work, (5) Daily huddles - coordination and issue resolution, (6) Learning - measure Percent Plan Complete (PPC), analyze reasons for failures. LPS increases PPC from typical 50% to 85%, reducing variability and improving productivity.