For more than 20 years, the authors of this volume have been involved in the creation and management of a successful 18-week partial hospitalization program: the Edmonton Day Treatment Program. This unique therapeutic model has proven both efficacious and time-efficient for patients with personality disorders - a population that traditionally has not responded well to treatment. The distinctive features of this program include its complete group orientation, its staff organization, and its psychodynamic approach. Throughout the volume, the authors interweave discussions of theory, clinical practice, and empirical research to explore the components that make this program successful. This therapeutic model has important implications for partial hospitalization programs, group therapy techniques, and the treatment of personality disorders. . The authors of this volume detail the day-to-day operations of the Edmonton Day Treatment Program and include its objective, structures, and guiding principles, with illustrations of group process and staff roles. The volume provides a comprehensive set of general principles and suggestions for effectively conducting a day treatment program, with presentations of common problems and ways to deal with them.