Extreme Programming Explored, by William C. Wake. Addison-Wesley, 2001. Foreword by Dave Thomas (The Pragmatic Programmer). This book grew out of the XPlorations series of articles. I wrote them as I was learning XP, and relating it to my own experience and practices.

Availability

There's a draft of the whole book available online. It doesn't reflect the final form of the book, but you can get a sense of what's changed since the articles were written.

The XPlorations series continues to grow. The table of contents below links to the original articles.

Table of Contents

Chapter 1. Introducing XP...........................................1
Programming, team practices, and processes.

Section 1: Programming

Chapter 3. What is refactoring?...............................29
"Refactoring: Improving the design of existing code."
--Martin Fowler

Section 2: Team Practices

Chapter 5. What’s it like to program in pairs?..65
Pair programming is exhausting but productive.

Chapter 6. Where’s the architecture?....................77
Architecture shows up in spikes, the metaphor, the first iteration, and elsewhere.

Chapter 7. What is the system metaphor?...........87
"The system metaphor is a story that everyone--customers, programmers, and managers--can tell about how the system works."
--Kent Beck

Section 3: Process

Chapter 9. How do you plan an iteration?........115
Iteration planning can be thought of as a board game.

Chapter 10. Customer, Programmer, Manager:
What’s a typical day?....................125
Customer: questions, tests, and steering;
Programmer: testing, coding, and refactoring; [without cube]
Manager: project manager, tracker, and coach.

 
Chapter 11. Conclusion...............................................143

Chapter 12. Annotated Bibliography......................145