1.5.1 XP
Extreme Programming is a discipline of software development based on values of simplicity, communication, feedback, and courage. It works by bringing the whole team together in the presence of simple practices, with enough feedback to enable the team to see where they are and to tune the practices to their unique situation.
The practices of XP can be shown in a single picture. These practices can be found in most of the Systems Engineering frameworks in some form or another.