Handbook of Effective Psydwtherapy is the culmination of 15 years of personal interest in the area of psychotherapy outcome research. In my view, this is one of the most interesting and crucial areas in the field: it has relevance across disparate clinical disciplines and orientations; it provides a measure of how far the field has progressed in its efforts to improve the effectiveness of psychotherapeutic inter vention; and it provides an ongoing measure of how readily clinicians adapt to scientific indications in state-of-the-art care. Regrettably, as several of the chapters in this volume indicate, there is a vast chasm between what is known about the best available treatments and what is applied as the usual standard of care. On the most basic level there appears to be a significant number of clinicians who remain reluctant to acknowledge that scien tific study can add to their ability to aid the emotionally distressed. I hope that this handbook, with its many delineations of empirically supported treatments, will do something to remedy this state of affairs.