Between 1961 and 1984, 262 patients with hyperthyroidism due to Graves' disease between the ages of 3 and 18 yr were treated in the author's clinic. This paper compares the results of different treatment methods. Initial treatment was surgery for 7 patients, radioiodine for 73, and an antithyroid drug for 182. Seven drug-treated patients subsequently had surgery. Of 14 surgically treated patients, 5 relapsed and received radioiodine, 5 became hypothyroid, 3 were lost to follow-up, and 1 remained euthyroid. Sixteen drug-treated patients were lost to follow-up; 7 are still taking drugs. Of the remaining 99 drug-treated patients not achieving remission, 92 received radioiodine, and 7 had surgery (1 later relapsed and received radioiodine). The principal reasons for abandoning drugs were toxicity, noncompliance, poor control, and failure to achieve sustained remissions. Of 61 drug-treated patients who achieved remission, 22 relapsed (21 were treated with radioiodine and 1 with drug). Remissions after antithyroid drug therapy persist in 39 patients, 2 of whom are now hypothyroid and 10 of whom have been in remission less than 2 yr. Of the 239 subjects whose treatment is complete, 191 (80%) ultimately had radioiodine. One radioiodine treatment eliminated hyperthyroidism in 163 patients, 2 treatments were effective in 17, and 3 treatments were effective in 1. The remaining 5 patients were lost to follow-up after radioiodine before the outcome of therapy could be determined. No increase in congenital abnormalities was found in 63 children of these patients, regardless of treatment. Radioiodine is a safe, simple, and economical therapy for patients with hyperthyroidism and is now considered the initial treatment of choice for such patients.