Practice-based evidence refers to research findings derived from clinical routine. As a complementary paradigm to randomized clinical trials, this evidence is collected through practice-oriented research with the goals of describing how mental health services are utilized and implemented, understanding how these services work or fail to work, and providing ways to improve practice. In contrast to traditional trials, practice-oriented research does not impose researcher-driven restrictions or prescriptions to clinical practice, which, for many practitioners, make research irrelevant to their work. By investigating psychological therapies as they are actually conducted in naturalistic settings, practice-oriented research stands as a strategy to foster a seamless integration between science and practice. In Practice-Based Evidence in the Psychological Therapies, practice-oriented researchers from different parts of the world and across a variety of clinical settings describe what led them to build their research programs, highlight studies they have conducted, and identify implications that can be derived from them. Among the key issues investigated are the effectiveness of treatment, routine outcome monitoring and clinical feedback, variables related to the client and the practitioner, therapist effects, mechanisms of change and therapeutic processes, and the context within which treatment takes place. The book concludes with a list of research, public policy, training, and clinical guidelines that should inform the delivery and investigation of mental health care. This work not only serves as a helpful source of information for practitioners, trainers, and administrators but also illustrates the value of practice-based evidence as a necessary component of the empirical foundations of psychotherapy.