This chapter illustrates how scope definition is the functional jumping off point for project planning. The formal project planning phase commences with various scope definitional activities designed to produce a clearer understanding of the project work units, deliverables, assumptions, and constraints. This activity leads to the development of a detailed work outline that represents the primary scope definition artifact for the project. Effective project work packages (WP) planning requires many items of information related to the activity in order to assess the content of the work and integrate it into the rest of the project. Recognize that a Work Breakdown Structure (WBS) will not always be fully decomposed to the WP level during the planning phase. The theory and concepts for a WBS are easy to understand; a basic question remains regarding how to identify the correct WBS structure for a particular project. Project team active involvement is imperative for moving the WBS through the development stage.