Blockade of different levels of the renin-angiotensin system has produced substantial benefits in terms of reducing cardiovascular morbidity and mortality. The introduction of aliskiren, a direct renin inhibitor, into the therapeutic arsenal has provided a new way of treating hypertension and protecting target organs. The antihypertensive efficacy of aliskiren is similar to that of other antihypertensive drugs and its safety and tolerability profiles are similar to those of placebo, even when used to treat obese hypertensive diabetics and elderly patients. Its use results in a persistent reduction in blood pressure and prolonged suppression of plasma renin activity, even after drug withdrawal. Data available from various clinical and preclinical studies indicate that aliskiren is capable of protecting against target organ damage, especially in diabetics. The promising results of clinical trials of aliskiren in hypertensive patients, which have looked at markers of organ damage in the kidneys and heart, confirm the importance of inhibiting the renin-angiotensinaldosterone system when seeking to reduce cardiovascular and renal morbidity and mortality. The current ASPIRE HIGHER clinical trial program was designed to evaluate, both indirectly (via effects on various markers) and directly (via effects on target organs), the ability of aliskiren to protect against organ damage. The results obtained will determine the role that direct renin inhibition can play in the treatment of arterial hypertension and, above all, in reducing cardiovascular morbidity and mortality.