Two cases of recurrent Cushing's syndrome after assumed total bilateral adrenalectomy are presented. Both cases were due to adrenal tissue left at the adrenalectomy. In the first case the lack of preoperative localization of the adrenal remnant caused severe postoperative complications. In the other patient localization of the adrenal tissue was achieved by scanning after administration of 131I-19-iodocholesterol. The reoperation was easy and the postoperative course smooth.