Although renin-independent hypermineralocorticoidism is an uncommon form of hypertension, its diagnosis provides the clinician with a unique opportunity in the field of hypertension, that is, to render a surgical cure or to achieve a dramatic pharmacologic response in the treatment of hypertension. Primary aldosteronism is the most common form of renin-independent hypermineralocorticoidism. The plasma aldosterone concentration to plasma renin ratio is an excellent screening test for primary aldosteronism, the diagnosis of which should be confirmed by demonstrating unsuppressible urine or plasma levels of aldosterone. The subtype of primary aldosteronism dictates the most appropriate therapy. Computerized imaging of the adrenal glands and adrenal venous sampling assist in distinguishing unilateral (requiring surgical treatment) from bilateral (requiring pharmacologic treatment) adrenal disease. The forms of mineralocorticoid excess considered in the hypokalemic hypertensive patient with low aldosterone values include congenital adrenal hyperplasia (11 beta-hydroxylase and 17alpha-hydroxylase deficiencies), deoxycorticosterone-producing tumor, Cushing's syndrome, primary cortisol resistance, and 11 beta-hydroxysteroid dehydrogenase deficiency (apparent mineralocorticoid excess syndrome). The I1 beta-hydroxysteroid dehydrogenase deficiency may be congenital or acquired (for example, ingestion of licorice or carbenoxolone).