Billions of dollars in business are lost annually because companies and software vendors fail to adequately test their software systems and products. These kinds of business losses are expected to continue as long as testing is considered just another check mark on a “To-do” list or a task given to employees who are on the bench and have nothing else to do. Testing is, in fact, a professional role that requires technical skills and a mindset that encourages the early discovery of the problems that represent real business risks. Although this textbook covers software testing in detail, many of the testing concepts and techniques it presents can be applied to other engineering disciplines and professions, as well as many personal pursuits.