OCD is a chronic, often disabling disorder in childhood that has been associated with increased rates of parental psychopathology and significant disruptions in family relationships and functioning. Preliminary studies suggest that ERP is an effective treatment for children with OCD although no controlled trials to this effect have been published. RT was selected as the comparison treatment because of its credibility as an anxiety treatment and familiarity to potential subjects. RT has been used as a comparison condition for at least 2 randomized controlled ERP trials for adult OCD and shown to be ineffective in treating this disorder. Although it has long been hypothesized that family participation in treatment may be helpful, this is the first controlled study incorporating a systematic manualized family treatment component.