What is the Last Planner System and How Does it Work?
The Last Planner System (LPS) is a workflow method developed by the Lean Construction Institute to increase worker productivity and accountability through tight scheduling and detailed group planning.
Last Planner is seen as a managerial approach on how to efficiently run a construction project. The guiding principle of the system is to ensure that each contractor and subcontractor on a construction site can manage their workload, while holding them responsible for the work they promised to complete.
This works through a collaborative exercise where the contractors and subcontractors specify the work they will accomplish and determine which phase of the project must be complete before the next phase begins. The advancement of workflows based on the timing and preparedness of the subsequent stage is known as Pull Planning; a practice adapted from Just-in-Time delivery.
When utilizing Pull Planning in LPS, there must be one person who's responsible for controlling when the next phase begins. This individual is referred to as the Last Planner. Typically on large-scale construction projects, each phase of the project will have its own Last Planner.
While this approach appears to assign greater responsibility to certain individuals over others, the nature of the Last Planner System is still collective. LPS succeeds in ensuring that every worker on a construction project is a stakeholder  by tracking and assigning accountability through entire workflows. Ultimately, every worker has a vested interest in completing their piece of the project because all phases are set up do be interrelated and interdependent.
This shared responsibility largely takes shape by following the five steps of LPS. They are as follows: 
1. Create Master Schedule
The first step in LPS is creating a master schedule that will dictate the flow of the entire construction project. Here, the lead contractors and subcontractors work together to determine major milestones and goals for the construction project. During this step, the entire project will be outlined in detail. Every task from the ground breaking to the ribbon cutting will be examined.
2. Create Phase Schedule
The second part of LPS is phase scheduling. This is where responsibility for each task is assigned to individuals, contractors and subcontractors. During phase scheduling, the project’s workflow is determined and the Last Planners work together to determine how long it will take to complete their aspects of the project. Once each Last Planner determines how long their task will take, they can form a more concrete schedule for the project.
3. Hold ‘Make Work Ready Planning’ Meeting
This phase in the Last Planner Systems is vital to ensuring that each person on a construction site has the necessary resources to complete their portion(s) of the project. The ‘make work ready planning’ meeting occurs for tasks that are to be complete four to six weeks from the date of the meeting. The purpose of this meeting is to identify any constraints that may come up during the project that could inhibit progress.
As constraints are identified, they get put into a logbook where each item can then be assigned to an individual who is responsible for fixing the issue by a certain date.
Issues such as materials not arriving on time, or not having the proper tools are some of the biggest constraints that construction sites face. Having a 'make work ready planning' meeting helps avoid unforeseen issues which can derail a project and send it over time and over budget.
4. Hold Weekly Check-ins
This stage in LPS happens every week during the construction project. It is meant to ensure that Last Planners and workers alike know what their upcoming tasks are for each week. During the weekly work planning meeting, every person who has been assigned a task will confirm that their job will be accomplished on time. While the completion time for each task was previously determined during phase scheduling, it is still important to verify during the weekly work planning meeting that these expectations will be met. If deadlines are not met the entire project could be thrown off schedule, incurring wasted materials, money, and time.
5. Hold Daily ‘Learning Meetings’ for Last Planners
The final stage of LPS occurs at the end of each work day. Before leaving the site, the Last Planners will convene to confirm that their tasks for the day were accomplished as assigned. If there was an issue that stopped the completion of their task, the Last Planners can collaboratively tackle the issue and work to put the project back on course. On a lean construction project, even small scheduling errors need to be fixed as soon as possible. If left unchecked, these could pile up and undo all the careful planning that came before.
The learning meetings are a perfect opportunity to perform a few different statistical analyses (or KPI's) to ensure that the project is on time and within budget. Minimally, these should include:
- Percent Plan Complete (PPC) - This analysis determines what percentage of the weekly tasks were accomplished. This can help Last Planers visualize what went wrong during the week so that they can make adjustments for the following week.
- Tasks Made Ready (TMR) - By measuring TMR the Last Planners can check if the phase scheduling process worked and is being followed. If there were fewer tasks made ready than planned, then the Last Planners should perform a root-cause-analysis to determine what went wrong and how they can improve.
- Tasks Anticipated (TA) - This analysis simply measures how many tasks were identified for the upcoming week. This provides the opportunity for Last Planners to see how much work is expected week by week, and allows them to understand what may have contributed to more productivity one week or less productivity in another week.
To conclude, LPS is a highly effective tool for construction management as it demands the use of multiple lean construction principles in a single system. It manages workflows and ensures that every single worker on a construction site is responsible for their piece of the puzzle. While the Last Planner System certainly requires practice to learn, refine, and implement, the productivity and efficiency that it affords makes the effort fully worthwhile.
If you would like more information about construction productivity improvement, please feel free to access our large-scale modularization fact sheet below: