The diagram known as an Entity Diagram or Entity Limiting Diagram is a tool that portrays individual functions and their link with "the outside world" - i.e. anything other than the contents of the functions themselves. All such links are input to, or output from, other system functions or functions outside the system. This technique views each function as an "atom" with links to other "atoms" without having to consider the entire "molecule". Entity Diagrams are particularly useful for interview management.

• See Conducting Interviews Kit in the Enablers