Chapter 4. Selecting Software Development Life Cycles

By definition, a project is a unique undertaking, resulting in a unique product. It follows, then, that a project is likely to employ a unique process for product development. How does a project manager go about the formulation of an appropriate process, or life cycle, to follow to achieve the project goals? Rather than starting from scratch with each project, the software manager is well served to begin with a generic, proven approach and customize it. There are multiple “starter” life cycles from which to choose. Some of the most widely used ones will be presented here, along with guidelines for selecting an appropriate one and guidelines for tailoring it to the needs of a specific project.

Chapter 1, “Introduction,” explained how and why the organization of this book follows a software product development life cycle. It's simply a way to discuss the 34 product, project, and people competencies in a logical order. Based on our process framework (Figure 4-1), defining the product (product competency 3) occurs before estimating its cost (project competency 14), so the former is presented before the latter. By following the process framework, we are also following the five major project phases published in the Project Management Institute's Body of Knowledge (PMBOK): initiation, planning, executing, controlling, and closing. Selecting and customizing a software development life cycle for a specific project occurs during the PMI planning phase.