Work Breakdown Structure (WBS)
Originally an American concept from the USA Defence Department which has been taken into use by other industries, not least construction. It is defined as a ‘deliverable-oriented decomposition of a project into smaller components’. The concept relies on the 100% rule in that by taking every part and successively subdividing it into manageable components in terms of size, duration, and responsibility (e.g., systems, sub-systems, components, tasks, subtasks and work packages) it will include all steps necessary to achieve the objective. It could be considered as a reverse Critical Path Analysis in the end, cost, time and deliverables are set initially and worked back from. This is actually the way most projects are structured it is just a formalized way of presenting those costs, stages and time-frame. A strength of the system is the intention to avoid overlaps and ensure that every component part is considered in context the whole and that though it is in some ways obvious it defines a path. It is a way to reduce ambiguity which can result in duplicated work or miscommunications about responsibility and authority and intentionally locks in budgetary considerations into the matrix. The WBS Dictionary describes each component of the WBS with milestones, deliverables, activities, scope, and sometimes dates, resources, costs and quality. In effect it works to plan outcomes, not actions.