A semiquantitative morphometric technique (point counting) was applied to the pituitary and adrenals taken at necropsy from 130 AIDS patients (4 women, 126 men, mean age 39 [22-71] years) to ascertain the nature, extent and location of the pathological lesions. Abnormalities were found in 32% of the pituitaries and 76% of the adrenals. Only 17 patients had normal findings in both organs. The predominant lesions were due to opportunistic infections or infiltration by Kaposi's sarcoma or non-Hodgkin lymphoma. The commonest finding was necrotizing cytomegalovirus adrenalitis (n = 68); in one third of the cases this had caused severe destructive lesions involving over 50% of the parenchyma. The almost total destruction of the adrenals noted in some cases suggests that cytomegalovirus adrenalitis may run a progressive course; its clinical significance has hitherto been underestimated.