Twelve patients with amenorrhea-galactorrhea and hyperprolactinemia are presented. The mean serum prolactin level was 175 ng/ml (range, 37 to 575 ng/ml). Basal gonadotropin levels were normal in all patients. Serum estradiol levels were normal in three women and reduced in nine. The response to luteinizing hormone-releasing hormone was normal in 10 patients and the response to clomiphene citrate was reduced in all women. Radiologic evaluations of the sella turcica and neurologic examinations were performed in all cases. Patients were treated with bromocryptine (2-bromo-alpha-ergocryptine, CB-154), 2.5 to 10 mg/day, for 5 to 35 weeks. In 10 patients normalization of the menstrual cycle was restored, and 9 patients were ovulatory. The galactorrhea ceased or was improved in all cases. Four patients who were treated for infertility became pregnant after one to three treatment cycles. In all cases prolactin levels were normalized (mean level, 10 ng/ml). Side effects were slight and were experienced only on initiation of therapy. The role of prolactin and the significance of normalization of plasma prolactin levels are discussed. Lowering prolactin secretion with bromocryptine allows resumption of normal gonadal function.