Page 46 - The Six Sigma Project Planner

Work Breakdown Structures (WBS)
The creation of work breakdown structures involves a process for defining the final and
intermediate products of a project and their interrelationships. Defining project
activities is complex. It is accomplished by performing a series of decompositions,
followed by a series of aggregations. For example, a software project to develop an SPC
software application would disaggregate the customer requirements into very specific
engineering requirements. The customer requirement that the product create x-bar
charts would be decomposed into engineering requirements such as subroutines for
computing subgroup means and ranges, plotting data points, drawing lines, etc.
Reaggregation would involve, for example, linking the various modules to produce an
x-bar chart and display it on the screen.

Creating the WBS
The project deliverables expected by the project’s sponsors were initially defined in the
project charter (p. 2). Deliverables metrics are given in Worksheet 6, Deliverables
Metrics (p. 19). For most Six Sigma projects, major project deliverables are so complex
as to be unmanageable. Unless they are broken into components, it isn’t possible to
obtain accurate cost and duration estimates for each deliverable. WBS creation is the
process of identifying manageable components or subproducts for each major
deliverable. The process is pictured in Figure 6.
Figure 6. WBS Creation Process Flowchart

Select a
deliverable
No

Can adequate
Are all cost duration
deliverables Yes estimates be
accounted determined for
for? this deliverable?
Yes

No
Draw WBS
diagram
Identify a
constituent
element of
this deliverable

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