This therapist guide describes a cognitive-behavioral family intervention for obsessive compulsive disorder (OCD) in young children (ages 5-8). Both parents and children are taught "tools" to help them understand, manage and reduce OCD symptoms. Exposure with response prevention (E/RP) is the main component of treatment. In E/RP, the patient is exposed to the feared situation, and the usual response (i.e. the ritual or avoidance behavior) is prevented until anxiety descreases. The corresponding workbook for families reviews skills learned in therapy and includes forms and instructions for home practice.