Behcet syndrome, a multisystem disorder characterized by ocular, mucocutaneous, articular, vascular, gastrointestinal, and neurologic abnormalities, is described in six pediatric patients. The patients ranged in age from 2 months to 11 years at time of onset. Several years were usually required before additional manifestations of the disease occurred. Aphthous ulceration was present in all six patients, arthritis in three, erythema nodosum in four, sterile cellulitis in three, gastrointestinal manifestations in five, neurologic manifestations in two, and genital or perianal ulcerations in three; ocular involvement was present in only one. There were no diagnostic laboratory studies, and, as in the adult population, no cause for Behçet syndrome was found. Patients had a variable response to corticosteroid therapy. Two patients who had significant morbidity and who responded poorly to corticosteroid therapy also received chlorambucil therapy, which appeared to provide improved control of signs and symptoms. Based on the prolonged interval between onset and the appearance of complete manifestations, Behcet syndrome may be more common in children than previously reported.