To assess the efficacy of fluoxetine for the long-term treatment of children and adolescents with anxiety disorders, including generalized anxiety disorder, separation anxiety disorder, and/or social phobia. Children and adolescents (7-17 years old) with anxiety disorders were studied in open treatment for 1 year after they completed a randomized, controlled trial (RCT) comparing fluoxetine and placebo. The follow-up phase assessments included clinician, parent, and child ratings with measures of global severity, global improvement, and anxiety symptoms. Subjects taking fluoxetine (n = 42) were compared with those taking no medication (n = 10) during follow-up on anxiety changes from the end of the RCT through the follow-up period. Statistical models included RCT assignment and follow-up psychological treatment. Excluded subjects took other medications (n = 4) or did not complete follow-up (n = 18). Compared with subjects taking no medication, subjects taking fluoxetine showed significantly superior follow-up outcomes on most measures, including clinician, parent, and child ratings. The results suggest that fluoxetine is clinically effective for the maintenance treatment of anxiety disorders in children and adolescents. A major limitation, however, was the lack of RCT methodology in the follow-up phase. RCTs are needed to determine the long-term risks and benefits of fluoxetine for this group.