EASE Project Management System
Schedule Work Breakdown Structure (SWBS)
A hierarchical scheme for labeling tasks. For example, A, A1, A1A, A1B, A2, B, ... EASE PMS provides for summary tasks (A, A1, B in the example above). A summary task is represented by the total span of the detail tasks below it.
Cost Work Breakdown Structure (CWBS)
A hierarchical set of cost categories. By tradition the numbering scheme 1, 1.1, 1.1.1, 1.1.2, 1.2, 2, 2.1, ... is used. The first number of the cost category typically accumulates costs for a physical item or a functional specialty. For an aircraft development program, 1 might be the aircraft, 2 ground equipment, 3 administrative activity, ... Activities under the first several levels will typically proceed for the life of the program (meaningless from a schedule point of view). The SWBS (properly chosen) will show program phases at the first summary level (Design, development, test, ...)
CWBS and SWBS serve different purposes. An SWBS provides schedule layering but does not provide for effective cost categories. For the CWBS, the opposite is true.
EASE PMS integrates SWBS and CWBS . A CWBS code can be an assigned property of each scheduled task. Costs will normally be summarized using the CWBS structure. Schedules will normally be summarized using the SWBS. But, you can use the CWBS for schedule selections and SWBS for cost summaries.