Behavior therapy for obsessive compulsive disorder.

Exposure in vivo and ritual or response prevention are the essential elements of behavior therapy for obsessive compulsive disorder. Naturalistic behavior therapy helped a fortunate few before the effective elements of behavior therapy were identified and systematically applied. Homework exposure and response prevention are essential and therapist accompaniment is seldom necessary. Homework sessions are planned by patient and clinician and written records facilitate treatment modifications during homework sessions. About a quarter of patients refuse behavior therapy, but 90% of the remainder achieve worthwhile gains with exposure and response prevention. Limited availability of behavior therapy is a substantial public health problem.