Getting to the Bottom of a Work Breakdown Structure

What is the WBS

The WBS is a visual, organizational tool showing all the scope on a project broken down into manageable deliverables as work packages. This allows the project manager and project team to break down a seemingly overwhelming project into pieces that can be planned, organized, managed, and controlled. The creation of the WBS is an effort to decompose the project outcomes into smaller component deliverables called work packages. Decomposition can be done using a top-down approach (starting at a high level), bottom up approach (starting at work package level), or by using a designated organization template. This helps ensure no deliverables are missed. The WBS is deliverable oriented – this does not mean that only customer deliverables are included. The complete scope of a project, including product scope, project scope, and project management efforts are included. Every WBS is unique, varies by project and even project manager, and should be created by the project team and project manager with input from other stakeholders. Each level is a breakdown of the previous level.

When is the WBS created and used

The WBS is the foundation of the project and should be created soon after the planning process starts. Almost everything that occurs in planning after the creation of the WBS is related to the WBS. For example, project costs and schedules are estimated at the work package level, and it can help a project manager and the team identify more risks by examining a project at the work package level.

The WBS can also be used throughout the project. A project manager can use the WBS as part of the integrated change control process to evaluate impacts of changes that relate to scope. When there is a scope-related change request, a project manager can use the WBS along with the project scope statement to determine if the request is within the planned scope of the project. Project managers can control scope creep by using the WBS to reinforce what work is to be done. The WBS can also be used as a communication tool when discussing the project with stakeholders (as a visual aid to demonstrate project progress) and can be used to help new team members quickly acclimate to the project.

Why is the WBS needed for the project

It should exist for every project; even adaptive projects should have a high-level WBS to help guide the backlog. Work breakdown structures can be reused for similar projects. As planning progresses, the team will use the WBS work packages to break down into schedule activities that are required to produce the work packages. This decomposition is part of schedule management and may be done at around the same time the WBS is being created but is not needed to baseline the scope. The WBS, WBS dictionary, and the project scope statement become the project’s scope baseline. Great project managers not only see the value of the information provided in the WBS. They also recognize the value of the effort involved in creating the WBS by ensuring all aspects of the project have been thought through. All deliverables should be represented in the WBS – if it is not in the WBS, it is not part of the project.

How is the WBS created

The WBS is a graphical representation of the project. Scope and work packages consist of nouns – these are the what of the project, not the how. No schedule or dependencies are shown. Levels of the WBS are often numbered for ease of reference. Those numbers can be used to help distinguish where a work package is in the work breakdown structure. The title of the project is at the highest level; the next level is usually the project lifecycle or phases; then deliverables for each phase; deliverables are broken down until work packages allow the project to be managed at the right level. Again, this can vary by project and project development approach.

Each work package in a WBS produces the phases’ deliverables, and each work package is described in the WBS dictionary. This describes the deliverable to be completed. Each work package has an owner, responsible for completing the work. On smaller projects, the WBS is often broken down into work packages that take between 4 and 40 hours to complete. Medium sized projects may have work packages that are 8 to 80 hours of work. Larger projects could have work packages that involve up to 300 hours of work.

Control accounts are sometimes found at higher levels within the WBS and is a tool that allows project managers to collect and analyze work performance data regarding costs, schedule, and scope. Control accounts may include one or more planning packages and provide a way to manage and control costs, schedule, and scope at a higher level than the work package. Each work package in the WBS is assigned to only one control account.

The WBS dictionary is a component of the WBS and allows the team to expand on the work packages in the WBS. This document provides a description of the work to be done for each work package and lists the acceptance criteria for each which ensures the resulting work matches what is needed. A project manager can use the WBS dictionary to prevent scope creep before work even starts, rather than dealing with scope creep while the work is being done. This is an output of the create WBS process. The document may be used as part of a work authorization system, which informs team members when their work package is going to start.


We provide helpful templates in most of our courses, and this is one of the most popular. Click here to download your own copy of the WBS template. Come back often to see other templates to help your projects thrive!

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