Twenty-five of 27 patients (93%) who had participated in a study of severe primary obsessive-compulsive disorder with onset in childhood or adolescence, were seen 2-7 yrs after initial examination (mean, 4.4 yrs). They were compared to a group of normal controls matched for age, sex and IQ and followed up for the same period. Continued psychopathology was striking for the patients, with only seven (28%), three males and four females, receiving no psychiatric diagnosis at follow-up. Seventeen subjects (68%) still had obsessive-compulsive disorder, 12 patients (48%) had another psychiatric disorder, most commonly anxiety and/or depression; neither initial response to clomipramine or any other baseline variable predicted outcome.