The practice of Test-Driven Development has proven to be one of the major differentiators in writing quality software. Based on 15+ years of experience, this book is my attempt to teach about the heuristics that are involved when writing loosely coupled, maintainable and readable unit tests. This book is for software developers who want to improve upon their existing skills for writing unit tests. You will learn how to build loosely coupled, highly maintainable and robust unit tests that are trustworthy and improve the overall code quality of your software applications. Although the examples in this book are written in C#, the principles and guidance are broadly applicable to other platforms and programming environments as well.