This part of the book introduces Patterns-Based Engineering (PBE). We start by defining PBE (Chapter 1) and then review a set of pattern implementation examples (Chapter 2). We continue with a case study to illustrate PBE in action (Chapters 3 through 7) and conclude with a discussion of the process aspects of PBE, including how it can integrate with Extreme Programming, Scrum, or OpenUP.