What works has side effects, and so does psychotherapy: Based on a large empirical study at the Danube University Krems (2007 - 2012), the book provides an overview of the risks and possibilities for avoiding harm through psychotherapy. Research findings on the topic and statements from key representatives of the recognized psychotherapy methods in Austria offer insight into a topic of quality assurance that has been neglected for too long. As long as psychotherapy does not address unwanted effects, it remains in a pre-scientific stage. The target audience includes psychotherapists, psychotherapists in training, psychotherapy patients, and those responsible for psychotherapeutic services in institutions.