SUMMARYA gonadotrophin responsive testosterone producing adrenal cortical adenoma in a 61–year‐old woman is described. Oophorectomy was performed before adrenalectomy as at first an ovarian origin of excess androgen production was suspected. The hypophyseal gonadal feedback system was studied after oophorectomy using LHRH before and after administration of ethinyloestradiol. After adrenalectomy this study was repeated using ethinyloestradiol at two dose levels and after premedication with testosterone. In this patient the LH feedback system behaved similarly to that observed in Klinefelter's syndrome and in patients with anorc