A type of behavioral therapy known as “exposure and response prevention” is very useful for treating OCD. In this approach, a person is deliberately and voluntarily exposed to whatever triggers the obsessive thoughts and then, is taught techniques to avoid performing the compulsive rituals and to deal with the anxiety.

Imagine that the person has a compulsion about washing their hands. These folks have trouble stopping hand washing once they start. The therapist would go in the bathroom with them, allow them to wash once, and then stop. The patient would have a lot of feelings and thoughts flood them at that time, and the therapist would teach them techniques to deal with those feelings and thoughts. A very good and inexpensive book on OCD is ''The Boy Who Could not Stop Washing.''