Functional Decomposition Process

What is Functional Decomposition Functional decomposition is the breaking down of a complex system into smaller pieces which can be more easily managed. In its most basic form is a simple hierarchical decomposition of the functions with associated performance requirements. Why would I use it It will make it easier to understand the system, its interactions and interfaces and is a useful tool in providing requirements insights for both analysis and design. It will also allow you to answer the users needs both stated and unstated by providing you with direct traceability to capabilities and on to requirements.