Testing is not possible without data. Input and output data, state data, and a test oracle are required. The authors provide a practical overview of test data management, along with concrete suggestions and assistance for the efficient provision of test data. Specifically addressed are: - Challenges, risks, benefits - Types of test data and methods for their generation - Legal rules and standards, data protection - Test data management process (artifacts, roles) - Integration into the organization - Test data tools. The book is aligned with the curriculum for the "Foundation Level Test Data Specialist" according to GTB and is suitable for self-study, thanks to a comprehensive glossary and consistent examples, as well as for use as supplementary literature for the corresponding training courses.