The glucocorticoid suppressible hyperaldosteronism (GSH) is a rare form of systemic hypertension. We report a family--a father and his two children--with this disease. GSH represents a peculiar form of primary hyperaldosteronism, with usually an absence of increase of aldosterone in response to upright posture, a sustained responsiveness of aldosterone to prolonged ACTH stimulation and high levels of two steroids, the 18-hydroxy- and the 18-oxocortisol. But the two main features of GSH which distinguish it from other causes of hyperaldosteronism are the prompt reversal of the features of mineralocorticoids excess by glucocorticoid therapy and the autosomal dominant mode of inheritance. Recent studies demonstrate that this disorder is caused by an abnormal structure of the aldosterone synthase gene. Treatment by glucocorticoid (usually 0.30 to 0.75 mg dexamethasone daily) can reverse hypertension and hypokaliemia.