Until recently, arterial stenosis and occlusion due to buildup of atherosclerotic plaque were recognized as the primary causes of coronary heart disease (CHD). Currently, CHD is viewed as a lifelong process of endothelial inflammation, thrombosis, and plaque instability and rupture. Lifestyle modification is an important first step in prevention of CHD, but even those patients who are the most committed to following a healthy diet and lifestyle frequently require the addition of drug therapy to further reduce risk. The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) reduce risk by lowering low-density lipoprotein cholesterol levels, as well as by stabilizing plaques, restoring endothelial function, and counteracting oxidative and inflammatory processes. Angiotensin-converting enzyme inhibitors also have antiatherogenic properties. Early, aggressive lipid intervention is the key to primary and secondary prevention of CHD.