This Handbook is the culmination of an interest in psychotherapy integration that led to our first professional collaboration in 1978. At that time we undertook (in research conducted for a doctoral dissertation by the second editor and supervised by the senior editor) to understand, from and within a psychodynamic perspective, the experiences of patients who had completed behavioral therapies. At that time, psychotherapy integration was a topic considered viable and interesting by only a few clinicians and scholars, with little communication among them and less awareness, concern, and appreciation on the part of psychotherapists in general. The situation today has changed. The appearance of this Handbook may be taken as a significant sign of maturation and legitimacy of work in psychotherapy integration. It is our hope and expectation that this volume will serve as an up-to-date and exhaustive overview of the status of ongoing scholarly and clinical work in the integration of the major schools of psychotherapy. The Handbook opens with a section that will provide the reader with an overview of the history, sociocultural context, and empirical status of the broad field of psycho therapy integration.