Primary aldosteronism is a frequent form of secondary hypertension that had long been considered relatively benign. Experimental and clinical evidence collected in the last two decades, however, has clearly demonstrated that this endocrine disorder is associated with excess cardiovascular and renal complications as compared to essential hypertension. These complications reflect the ability of inappropriate elevation of plasma aldosterone to cause tissue damage beyond that induced by high blood pressure itself, thereby setting the stage for major cardiovascular and renal disease. Because of the impact of elevated aldosterone on organ damage, goals of treatment in patients with primary aldosteronism should not be limited to normalization of blood pressure, and prevention or correction of organ complications is mandatory. Treatment with mineralocorticoid receptor antagonists or unilateral adrenalectomy is the respective options for treatment of idiopathic adrenal hyperplasia or aldosterone-producing adenoma. Last years have witnessed a rapid growth in knowledge concerning the effects of these treatments on cardiovascular and renal protection. This paper is an overview of the cardiovascular and renal complications that occur in patients with primary aldosteronism and a summary of the results that have been obtained in the long term on cardiovascular and renal outcomes with either medical or surgical treatment.