Recently, both researchers and clinicians have focused their attention to the blockade of the renin-angiotensin system (RAS). Their efforts resulted in discovery of ACE inhibitors. ACE inhibitors proved to be effective antihypertensive drugs. However, their excellent antihypertensive efficacy has been limited by frequent occurrence of adverse effects, among which cough occupies a prominent place. Angiotensin II receptor antagonists could completely block RAS, having significantly less adverse effects than ACE inhibitors. Clinical studies have demonstrated that angiotensin II receptor antagonists are equally effective in the treatment of hypertension as diuretics, beta blockers, calcium antagonists and ACE inhibitors. Also the studies showed angiotensin II receptor antagonists to have an additional advantage, i.e. the frequency of their adverse effects matches that of placebo. All today available angiotensin II receptor antagonists--losartan, valsartan, irbesartan, candesartan, eprosartan, and telmisartan--equally lower both systolic and diastolic pressure. This new class of drugs can be used as monotherapy or can be combined with other antihypertensive drugs, especially with diuretics. Trials now underway will demonstrate whether angiotensin II receptor antagonists can prevent target-organ damage and reduce cardiovascular morbidity and mortality.