Foundation
The Central Problem LPS Solves
Traditional construction scheduling asks: "What SHOULD happen this week?" — and then measures why it didn't. The Last Planner System shifts the conversation to: "What WILL happen this week — and what do we need to remove to make that promise keepable?"
The gap between what should happen and what can happen is where most project delays live. LPS makes that gap visible, assigns ownership to close it, and tracks whether promises are being kept — creating a feedback loop that improves reliability week over week.
Planning Hierarchy
Five Levels of LPS Planning
LPS operates across five nested planning levels — each one progressively shorter in horizon and higher in commitment certainty. Our app implements all five.
The high-level milestone plan — project phases, major deliverables, key hand-off dates. Set at project start by the GC and owner. Updated infrequently. Defines the boundary conditions for all planning below it. Not a commitment document — it is an intent document.
A collaborative session where all trades work backwards from a phase milestone — asking "what do I need from you before I can do my work?" Each trade makes promises and requests, surfacing hand-off dependencies. Conducted once per major phase. The output is a network of swim-lane commitments, not a Gantt chart.
A rolling window of work expected in the next 3–6 weeks. The primary tool for constraint removal — every task is reviewed weekly to determine whether it is READY (all constraints removed) or CONSTRAINED (needs action before it can be committed). Work that is not ready never enters the Weekly Work Plan.
The core commitment document of LPS. Only work that is READY — all constraints removed, resources assigned, prerequisites complete — appears here. Each task is a personal promise made by the Last Planner (foreman, trade lead). Weekly PPC is measured against this plan. "Should" does not appear here — only "will."
Short daily stand-ups (15 min max) where crews confirm the day's plan and surface emerging constraints. In remote or distributed projects — like Pacific Tower's workflow — this level is replaced by structured evening field reports submitted via Telegram, WhatsApp, or Email, analyzed by the AI agent overnight, and validated by Project Controls in the morning.
The Core Metric
Percent Plan Complete (PPC)
PPC is the only metric LPS introduces. It measures the reliability of planning — not productivity, not cost, not schedule adherence. A project with high PPC is a project whose teams keep their promises. The research correlation: high PPC projects consistently deliver faster and cheaper.
| Industry average | 54–65% |
| LPS minimum target | ≥ 75% |
| Good LPS practice | 80–85% |
| World-class projects | 85–95% |
When a committed task is not completed, LPS requires recording why — not to assign blame, but to improve the planning system itself.
{[ {label:"Previous work incomplete",pct:30,color:"#f39c12"}, {label:"Over-committed (too many tasks)",pct:25,color:"#e74c3c"}, {label:"Change in work plan",pct:20,color:"#4a90a4"}, {label:"Resources unavailable",pct:15,color:"#8e44ad"}, {label:"Outside constraint",pct:10,color:"#16a085"}, ].map(c=>`Constraint Management
The Make-Ready Process
The most powerful tool in LPS is the constraint removal discipline, sometimes called the Make-Ready process. Before a task can move from Lookahead into the Weekly Work Plan, every constraint must be identified, owned, and resolved.
Seven Constraint Categories
- Design — drawings, specs, RFIs not yet answered
- Submittals — shop drawings, material approvals pending
- Materials — procurement delivery not confirmed
- Labor — crew not available or not yet assigned
- Equipment — crane, pump, tool not available
- Prerequisite work — prior task by another trade not done
- Space — physical access not cleared for the crew
Make-Ready Weekly Routine
- Pull all tasks entering the 3-week Lookahead window
- Assign an owner to every identified constraint
- Set a resolution due date before the task's planned start
- Review constraint status at the weekly planning meeting
- Only mark a task COMMITTED when all constraints are green
- If a constraint cannot be removed in time, push the task — do not commit and miss
Context
LPS vs Traditional CPM Scheduling
Critical Path Method (CPM) and Last Planner System are not competing tools — they serve different purposes. CPM answers "what is the plan?" LPS answers "will the plan actually be executed?"
| Dimension | CPM / Traditional | Last Planner System |
|---|---|---|
| Planning horizon | Full project, months ahead | Multi-level: phase → week → day |
| Who makes commitments | Scheduler in office | Foremen and trade leads in the field |
| Constraint handling | Assumed resolved by schedule | Explicitly tracked and owned |
| Reliability metric | Schedule variance (after the fact) | PPC measured weekly, cause recorded |
| Collaboration model | Top-down task assignment | Promises and requests between trades |
| Learning loop | Post-project lessons learned | Weekly variance analysis → system improvement |
| Used alongside LPS? | Yes — CPM sets master schedule | LPS executes against it reliably |
Remote Adaptation
LPS for Distributed & Remote Projects
The original LPS was designed for co-located teams and physical sticky-note boards. Large projects — especially those with HQ teams managing remote field crews — require a digital adaptation that preserves the intent of each level without requiring everyone in the same room.
| Phase Pull Sessions | Run via video conference with a shared digital board. Each trade lead joins and places their promises and requests in real time. The swim-lane output is captured digitally and loaded into the app's Phase Pull Planning tab. |
| Lookahead & WWP | Managed centrally by Project Controls using the app. Foremen review their tasks during the daily field report submission — confirming status, flagging new constraints. |
| Daily Huddle → Field Report | Replaced by structured evening reports via Telegram, WhatsApp, or Email. The n8n workflow captures the message, attaches metadata (channel, timestamp, GPS if available), and routes it to the Report Inbox. |
| AI Agent Analysis | The HQ AI agent reads all incoming reports each evening, cross-references the current Lookahead and constraint log, and prepares summaries and recommended actions — ready for morning review. |
| Human-in-the-Loop | Project Controls reviews the AI analysis every morning before the workday begins. Each report can be validated, overridden, or escalated. No AI output enters the planning system without human sign-off. |
Evidence Base
What the Research Shows
Documented Project Outcomes
- Sutter Health CPMC (San Francisco) — 30% reduction in planned project duration using LPS on a $2.4B hospital project
- Boldt Company studies — LPS projects averaged 89% PPC vs. 54% industry baseline
- Multiple UK NHS hospital projects — LPS reduced construction phase by 15–25% vs. traditional CPM-only scheduling
- Lean Construction Institute findings — teams with PPC above 75% consistently outperform on cost and schedule
Why It Works
- Social commitment — promises made by trade foremen carry more weight than tasks assigned by a scheduler
- Constraint visibility — problems surface 3 weeks before they impact work, not the day of
- Learning loop — weekly PPC + cause analysis continuously improves the planning system
- Pull vs push — downstream trades pull work forward only when they are ready, preventing inventory buildup and rework
- Right level of detail — commitments are made at the right level of precision for the time horizon
Apply the methodology
Open the Daily Controls App
All five LPS levels implemented for Pacific Tower NYC — 32 floors, Week 10 of 44.