This post takes a brief look at each of the five levels within the Last Planner® System1 (LPS). The system was designed and developed through action research by Glenn Ballard and Greg Howell in the early 1990s2. The purpose of LPS is to produce predictable workflow and rapid learning through social conversations, clear communication, better coordination and commitment based planning. Many perceive LPS as a tool that is only used during the construction phase of capital projects. However, it is also used during (but not limited to) the procurement, design, commissioning and decommissioning phases as well as in other project scenarios such as corporate software rollout and shipbuilding. It can be used anywhere coordination between humans is required3. LPS is a gateway to lean behaviours4 and the foundation of lean project delivery5. It is a system of interconnected parts used at five levels of production planning and control “... omission of a part (of LPS) destroys the system's ability to accomplish functions.”3 To maximise the effectiveness of LPS, teams need to embrace all elements of the system. Recent research shows that teams generally fall short of using the LPS in full6.
LPS coaches Dan Fauchier and Dave Umstot compare the SHOULD, CAN, and WILL levels of LPS to the level of detail you see when looking out of a plane at various altitudes – the closer the plane gets to the ground the more detail you can see. The five levels of the LPS is illustrated in Figure 1.
Figure 1: LPS Schematic (after Glenn Ballard - used with permission)
Level 1: What SHOULD be done?
The first level includes milestone planning for the entire project (30,000ft view from a plane) and phase planning approx. 2 months long (10,000ft view) to create a shared understanding of scope, key milestones, major constraints, and a logical sequence of work. Figure 2 illustrates a milestone and phase plan. Pull planning is used to identify the project’s strategy, clarify work handoffs and the Conditions of Satisfaction (CoS) for acceptance of work. It also communicates how the Last Planners®1 work impacts each other's’ work. The goal is to create a shared understanding of how the project SHOULD be delivered and create an environment to plan and coordinate collaboratively. Pull planning helps to deliver bad news early by focusing on handoffs while working back from specific milestones. This typically identifies bad news such as grey areas in a contract between trades or gaps in project scope at front end planning and procurement stages. But when is bad news really good news? When it comes early. This allows the team to explore alternative solutions at the wall rather than in the field.
Figure 2: Milestone and phase pull plans (image source: Paul Ebbs)
Level 2: What CAN be done?
Construction projects generally use a six week lookahead plan. However, LPS uses a lookahead window and make ready planning. The difference is rather than just looking ahead and asking the question: is this task ready to start? Every activity is actively screened for constraints. This is a path clearing exercise. I encourage teams to use each of the 8 Flows7 shown in Figure 3 as triggers. Activities are planned in further detail - similar to a 1,000ft view from a plane. The make ready plan is then created directly from the phase plan. The length of the plan depends on the length of time required to remove the longest constraint. Typically it is 6 to 8 weeks long. This ensures the work that SHOULD be done CAN be done.
Figure 3: The 8 Flows of lean construction (Source: Christine Pasquire)
The constraint log records any actions required by whom and the Last Responsible Moment (when) to remove constraints. By ensuring each activity is screened for constraints against the 8 Flows, work that CAN be done then converts into what WILL be done.
Level 3: What WILL be done?
A reliable Weekly Work Plan (WWP) evolves from the make ready plan as all activities are understood to be constrain free. Then, reliable promises are made for the next two weeks of work - creating predictable work. Promises after this period are not sought as it is too far in the future to make reliable predictions. Examples of reliable promises are: “I will do x by y date/time”; “I will do this if…” or by simply saying “No”.
There are five rules for making a reliable promise8 . Given the rules below, Last Planners must say "NO" if they have any doubts about achieving them. This triggers a path clearing activity. Otherwise you are stating "YES" without qualification and it becomes their commitment and is used as the activity metric - Percentage of Promises Completed (PPC).
- Access competency before making promise
- Understand the condition for satisfaction
- Including a realistic time for completion, quality/safety considerations etc.
- Ensure capacity is available and allocated
- Ensure unspoken conversations conflicting with the promise are not taking place
- Accept responsibility for failure and re-review the process for learning
Figure 4 shows a typical WWP board.
Figure 4: Typical Weekly Work Plan (WWP) board (image source: Paul Ebbs)
The different colour tags (Post-its®) in Figure 4 illustrate the different trades - demolition, electrical, mechanical etc. The diamond shaped tags show the missed commitments from the previous weeks WWP board. It also shows PPC and a workable backlog (or Plan B) of tasks that will be done in the event that new constraints arise to Plan A. The LPS is resilient and agile enough to facilitate the inevitable changes to plan. Plans are kept real and the WWP boards reflect the actual ongoing work in a colourful easy to read visual format. An additional benefit of the WWP boards is that the status of a project and/or activity is quickly established.
Level 4: What was done i.e. DID?
The status of commitments get updated, managed and tracked at daily huddles. This supports learning and re-planning if and when it is necessary to keep the plan real. When the activity is complete, the Last Planner who owns the tag marks it as “done (/)”. Then either the “next” person waiting for the work or else the site manager/superintendent mark it as “done, done (X)”, only when they can confirm the activity is 100% complete. This has a knock on effect of reducing rework because the work gets handed off right first time.
At Level 4, new constraints arise daily. Addressing these helps ensure a reliable workflow is maintained. PPC is calculated daily and trended weekly using Pareto charts. It acts as a measure of how well the team is working and coordinating action together. However, note that PPC must only be used to measure team performance rather than individual partners because missed commitments must always be focused on system failures i.e. Why not Who. Deming9 states that approximately 94% of the time the system is at fault. The Reason for Missed Commitment (RMC) category list must reflect system issues. The content of the RMC list will vary between teams and also depends on the type or phase of project that LPS is being used on. A typical construction phase example is below. The number assigned to the RMC list (and 5 Why analysis where possible) gets logged on the back of each activity tag that is missed (diamond shapes in Figure 4). The issues with the greatest impact on the schedule get investigated ASAP using a dedicated root cause analysis workshop.
- Bad planning
- Prior work
- Design issue
- Failed inspection
- Materials not available
- Equipment not available
- Labour not available
- Information not available/updated
- Contracts/change orders
- I forgot
- Unforeseen conditions
- Misunderstanding/unclear CoS
Can you see how this RMC list relates to each of the 8 Flows I mentioned before? This emphasizes the value of the make ready process and how learning gets incorporated into the system at each level.
Level 5: What the team needs to LEARN from..?
Learning from plan failures (root cause analysis) is critical to prevent the same issues happening again. This improves the system as a whole and the flow of the project. The purple arrows in Figure 1 indicate how learning takes place at every stage. This happens through plus/deltas (what was good/what can be improved), takeaways (what did you learn today), 5 why analysis of RMCs, and also root cause analysis workshops.
This post provides a very high level overview of the key levels of the Last Planner System. The LPS is a socio-technical system that fosters many of the desired lean behaviours. While the premise behind the system is simple, the benefits are often not realised because the use of LPS fades off or teams fail to utilise the LPS in full. For sustainable results the correct use of all LPS levels - should, can, will, did, and learn - are critical to success. However, to foster success I strongly recommend engaging with a competent LPS coach - either internal in your organisation or an external coach. In my experience, the first exposure teams receive to the LPS is critical to success. A poor approach often results in the team (or individuals within the team) rejecting LPS because they have not been trained and coached sufficiently. The coach will help the team learn to use all levels of LPS and support the team as required.
1. The terms Last Planner® System and Last Planner® are registered trademarks of Lean Construction Institute. See www.leanconstruction.org
2. Emmanuel Daniel and Christine Pasquire (2016). The History and Development of the Last Planner System. Lean Construction Blog 4 May
3. Glenn Ballard and Iris Tommelein (2016). Current Process Benchmark for the Last Planner System.
4. Dan Fauchier and Thais Alves (2013). Last Planner® System Is the Gateway to Lean Behaviors. Proceedings 21th Annual Conference of the International Group for Lean Construction. Fortaleza, Brazil, 31-2 Aug 2013. pp 559-568.
5. Glenn Ballard (2008). The Lean Project Delivery System: An Update. Lean Construction Journal.
6. Emmanuel Daniel, Graham Dickens, Christine Pasquire and Glenn Ballard (2016). The Relationship between the Last Planner® System and Collaborative Planning Practices in UK Construction. Engineering, Construction and Architectural Management. ISSN 0969-9988 (Forthcoming).
7. Christine Pasquire (2012). The 8th Flow - Common Understanding. Proceedings 20th Annual Conference of the International Group for Lean Construction.
8. Hal Macomber and Greg Howell (2003). Linguistic Action: Contributing to the Theory of Lean Construction. Proceedings 11th Annual Conference of the International Group for Lean Construction. Virginia, USA.
9. W. Edward Deming (2000). Out of crisis. Reprint. MIT Press.