For diagnosis of adenomas in primary aldosteronism CT proved to be helpful. Although microadenomas have to be ruled out by selective venous sampling from both adrenal glands adenomas down to 8 mm in diameter can be visualized. Scintigraphy does not always permit reliable differentiation of unilateral adenoma from bilateral hyperplasia. -- in endogenous Cushing's syndrome adrenal carcinomas are underlying etiologically in about 10% of the cases. Since carcinomas are detected easily by CT it should be performed in the first place. Whereas adenomas and hyperplasia are easily diagnosed by scintigraphy carcinomas may escape scintigraphy. -- Pheochromocytomas, if situated in the vicinity of the kidneys, can be localized safely by CT. Contrary to adenomas, carcinoma and pheochromocytomas may be detected by CT without difficulty because of their size.