OBJECTIVE To study the clinical spectrum of Behçet's disease (BD) in childhood, and to report our experience of using thalidomide. METHOD Ten children, diagnosed with BD, were studied retrospectively. RESULTS The median (range) age at first presentation was 4 (1.2-12.0) yr, at diagnosis was 11 (3-15) yr and the follow-up period was 4.1 (0.6-6.3) yr. Oral ulcers were present in all patients (100%), genital ulcers were present in six (60%), peri-anal ulcers were present in three (30%), skin manifestations were present in nine (90%), intracranial hypertension was present in two (20%), mild gastrointestinal symptoms were present in five (50%), joint symptoms were present in six (60%), ocular lesions were present in five (50%), but only one child had anterior and posterior uveitis. Therapeutically, a range of drugs was used, including colchicine, that resulted in good responses in five children. Thalidomide (1 mg/kg/week to 1 mg/kg/day) was used in five children who were unresponsive to other immunosuppressive agents. It resulted in complete remission in three children and less frequent milder oral ulcers in two. Neuropathy developed in two children and in one it was irreversible. CONCLUSION BD in children is similar to the disease in adults. Thalidomide provided a useful therapeutic option for severe oral and genital ulceration which was unresponsive to other therapies. Awareness of the danger of axonal neuropathy and teratogenesis at all times during thalidomide therapy is crucial. A low dose is probably as effective as higher doses.