Book excerpt: This Cognitive Behavioral Analysis System of Psychotherapy (CBASP) Group Manual is a treatment guide for mental health professionals working with persistently depressed individuals. The manual provides a clear step-by-step application of CBASP as a group treatment modality, the research findings supporting the effectiveness of this treatment, and suggested methods of assessing outcome as well as possible applications or adaptations of the treatment to different settings and disorders. This manual is accompanied by a separate workbook for patients.