Studies of urinary 17-ketosteroids, corticosteroids and pregnanetriol, as well as chromatographic analysis of the major C19 urinary steroids, were carried out in 39 patients with polycystic ovaries pre- and postoperatively. Total 17-ketosteroid excretion in the polycystic ovary patients ranged from 5.4 to 30 mg/day; the values did not correlate with androgenic manifestations. Few of the patients showed any significant elevation of dehydroepiandrosterone or C10O3 steroid excretion, and the excretion patterns of C19O3 steroids were very variable, both in the group as a whole and in individual subjects. None showed significantly elevated corticosteroid or pregnanetriol excretion.