None of the participants had received previous treatment. Both types of treatment were administered for 12 weeks, followed by a measurement of outcomes over a 9-month follow-up period, during which there was no active treatment. Participants were 9-17 years old (n=40) who met the DSM-IV diagnostic criteria for OCD. Subjects were recruited from October 2000 through April 2002. Twenty were randomly assigned to receive GCBT, and 20 were randomly assigned to receive sertraline. Subjects were assessed before, during, and after treatment. Posttreatment assessment were at 1, 3, 6, and 9 months after treatment ended. The primary outcome measure was the children's Yale-Brown Obsessive-Compulsive Scale. Repeated-measures analyses of variance were conducted. Findings show that both GCBT and sertraline produced significant improvement in OCD symptoms after 12 weeks of treatment. After the 9-month follow-up period, subjects in the GCBT group had a significantly lower rate of symptom relapse than those in the sertraline group. These findings indicate that treatment with GCBT may be effective in decreasing OCD symptoms in children and adolescents and should be considered as an alternative to either individual cognitive-behavioral therapy or the use of a medication such as sertraline. 3 tables, 1 figure, and 31 references