The book addresses the topic of testing—not from the perspective of developers, but from the viewpoint of professional users. Using a bank as an example, it identifies approaches and experiences that illustrate the importance of testing. In fact, testing at the beginning of the cycle is crucial, as this is where the most knowledge can be gained. The volume describes all important aspects from conception to execution in a practical manner. The author aligns with the IT system lifecycle (introduction, maintenance, decommissioning).