We present a 39-year old female with a benign adrenal tumor characterized by autonomous secretion of cortisol, androgens, and aldosterone. The patient presented with a 4-year history of hypertension and severe hirsutism. Baseline investigations revealed elevated testosterone, androstendione, and 17OH progesterone with normal levels of dehydroepi androsterone sulfate. CT of the adrenals revealed a 2.5x3.0 cm tumor with characteristics of an adenoma on the left adrenal gland. Pelvic ultrasound was normal. Further investigations revealed suppressed basal ACTH levels, loss of diurnal rhythm of cortisol, and failure to suppress on low dose dexamethasone suppression test, suggesting autonomous cortisol secretion by the tumor. She had an exaggerated response of 17OH progesterone to ACTH, implying reduced 21-hydroxylase activity. An elevated plasma aldosterone concentration to plasma renin activity ratio was suggestive of hyperaldosteronism, which was confirmed by failure of aldosterone to suppress to a formal saline infusion test. Complete clinical and biochemical remission of the disease was observed after left adrenalectomy. Histology confirmed the presence of an adrenocortical adenoma. The patient developed multiple sclerosis 6 months after the operation. The flare-up of an autoimmune disease (multiple sclerosis) postoperatively could be coincidental or possibly related to the high normalization of the high cortisol levels acting as a precipitating factor.