Stage 1 – Work Breakdown Structure (WBS)

This is step 1 of a guide to project planning covering 4 steps. You can access steps 2 - 4 here. Stage 2 - Precedence Diagrams, Stage 3 - Estimate Effort and Schedule, Stage 4 - Resource Allocation and Levelling.
Work Breakdown Structure (WBS). A hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables. (PMI Lexicon of Project Management Terms)
To plan a project you need to be sure that you have captured all of the deliverables and tasks that make up the finished project in a Work Breakdown Structure (WBS).
The sum total of the parts of a project is the project scope, the WBS represents the project

How to create a Work Breakdown Structure

The best way to produce a WBS involves post-its and a blank wall.
Get your team together and ask them to spend 10 – 15 mins listing out all of the project tasks that they can think of.
If you have a large project it may help to split the work into work streams or groups.

To get things moving ask team members to focus on their tasks or their departments tasks. Write out your own project management tasks as well.

When you can see plenty of post-its and people are starting to slow down, Write the end product of the project and place it at the top of the wall or white board. Underneath the final product put up post its representing the key deliverables or work streams.

For example; the key deliverables of a software implementation Work Breakdown Structure might look like this.
work breakdown structure (WBS)

See more real-world examples of Work breakdown structures (WBS).

Once you have the key deliverables, ask your team to add their tasks beneath each main deliverable. You will have a mix of products, sub-products and tasks. Organise the products in a hierarchy so that each product is broken down into its component parts. Using the software project example you might have something like this:

Example Work Breakdown Structure

example of a work breakdown structure, decomposed to 4 levels, with a unique numbering system for each workpackage. There are two annotations: one calls out the numbering, the other points out how each component of the WBS can be traced up to it's parents.
Don’t get hung up on how the tasks should be grouped. The key here is too identify, as far as possible, everything that needs to be done to deliver the project. See a WBS Checklist
The example above breaks down just two of the work streams and you can probably see other deliverables that could be added beneath the lowest level.

For example:
Look at 1.1 Staff Trained then 1.1.3 Training Prepared. Under Training Prepared there are two work packages: Venue Booked and Materials prepared. To book a venue you may also need to:
  • view venues,
  • gather quotes,
  • and complete the paperwork.
These tasks could be added to the WBS (depending on how much decomposition is needed for the project).
5th level added to an example work breakdown structure for preparing for a training course

Similarly, to complete software installation, permissions may be required for changing firewall settings, and a specific resource may need to be booked to make the permission changes.

How low should the Work Breakdown Structure go?

At some point in this process you are going to wonder or be asked how far you need to breakdown the tasks. For lowest level tasks you should be able to:
  • identify a single point of responsibility for completing the task
  • clearly distinguish the task from other pieces of work
  • see interfaces/dependencies with with other tasks
  • estimate the effort required to complete the task
Get a checklist to assess your WBS.

Breaking down the work to the right level will ensure you develop a detailed, high quality project plan.

In the next stage the Work Breakdown Structure is used to create a Precedence Diagram. Stage 2 - sequence deliverables in a Precedence Diagram.

Work Breakdown Structures - references and further reading

PMI Lexicon of Project Management Terms, 2012, PMI. [online] Available at: [Accessed 18 June 2015].

WBS Checklist - Download a checklist for reviewing a WBS.

WBS Dictionary - Download a Free Template in Excel.

Excel WBS Template - Download an Excel WBS Template

FREE Online WBS Template - Free Online Template for creating a WBS