The importance of renin-angiotensin-aldosterone system (RAAS) in diseases such as hypertension, congestive heart failure and chronic renal failure has long ago been recognized. It has also been established that inhibition of RAAS, using inhibitors of the angiotensin-converting enzyme (ACE) or angiotensin II receptor blockers (ARB), is an effective way to intervene with the pathogenesis of these disorders. Renin inhibitors block the RAAS at the highest level, at its origin, and might thus offer a new exciting approach for pharmacotherapy of arterial hypertension. Aliskiren is the first in a new class of orally active, non-peptide, low molecular weight renin inhibitors, and so far the only renin inhibitor that has progressed to phase III clinical trials. This review summarizes the available data on the pharmacokinetic and pharmacodynamic properties of aliskiren and its clinical development for treatment of arterial hypertension.