Angiotensin receptor blockers are one of several drug classes that act by interfering with activity of the renin-angiotensin axis. Drugs in this class are as effective as angiotensin-converting enzyme inhibitors in the reduction of blood pressure in hypertensive patients. Results from a series of outcomes trials increasingly support the use of drugs in this class as cardioprotective and renoprotective agents in patients with heart failure, diabetic nephropathy, and post-myocardial infarction.