The first thing you need to do when building a project
schedule is to create a Work Breakdown Structure (WBS). Creating a WBS allows
you to look at the project at a high level and then break it into smaller pieces
until you can get the full picture of the totality of work that needs to be
performed. The project manager may be able to create a draft of the WBS as a
starting point or the entire team (and clients) can create a WBS in a group
exercise.

The general process for creating a WBS is as follows:

  • State
    the name of the entire work effort. This is the top level of your WBS
    (generally called level 0.0)
  • Look
    at the large chunk of work and break it down into smaller pieces that
    together represent the larger chunk. You might break a large piece of work
    into two smaller parts, five smaller parts, or whatever number of smaller
    parts makes sense. Sequencing is not important at this time.
  • After
    you finish your work breakdown, do a quick estimate of the effort required
    to complete each individual work component to see if the work effort is
    larger than the “estimating threshold.” This estimating
    threshold is based on how large you want the final activities to be. It’s easier
    to manage four forty-hour activities than one 160-hour activity. For a
    typical business project, we recommend that you try to break the work into
    activities that are no larger than 80 hours of effort, but this number
    could be higher or lower based on the size of your project.
    You should also look at each chunk of work to determine whether it’s
    simple enough that you understand it. This is important because the work
    at the lowest levels of the WBS (work that is not broken down any further)
    will be moved to the schedule. If you have work on the schedule that’s vague
    and not understandable, you won’t be able to assign the work to a team
    member for completion.
  • Look
    at each of the work components that you have broken down from the higher
    level and apply the two checks from step 3. If either of the answers is “no”
    then you would repeat steps 2 and 3.

The process of breaking the work components into their lower
level set of activities (steps 2-3 above) should continue until all work
components are represented as granularly as necessary, with no activities
having estimated effort larger than the estimating threshold and where you
understand all of the work. This is when the WBS is complete.

There is a caveat to the work breakdown process above. If
your project is very large, it’s also likely that you may not know enough to be
able to break all of the work down to the level described above. This may still
be okay as long as those higher-level chunks of work are far in the future. In
this case, you can leave the work at the higher level until you get closer to
executing the work. When this higher level work is within three months of
executing, you should know enough to be able to break the work down at a more
granular level.