This book teaches programmers how to make Test Driven Development (TDD) work in their organization. TDD is unique because it forces the programmer to write tests for code before the code is actually written. This process is the reverse of how software testing has traditionally been conducted, but TDD ensures that software is produced more efficiently. A test-first mentality allows the programmer to define, specify, illustrate, limit, and drive the code, resulting in documented, tested, code that is as simple and lean as possible. The book also presents tools and techniques, and all major points are supported by numerous examples (including an entire project, end-to-end) and exercises.