Until the recent introduction of the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), the potential effect of cholesterol lowering on the prevention of clinical manifestations of coronary disease was a matter of debate. In trials conducted before the introduction of statins, cholesterol levels were lowered, on average, by only approximately 10%, resulting in prevention of coronary events but with no effect on total mortality rates. However, statins have been able to reduce low-density lipoprotein cholesterol levels by a mean of roughly 28%, significantly decreasing both relative and absolute risk levels of coronary events and total mortality. These benefits have been demonstrated not only in middle-aged men but also in women and patients aged >65 years. Aggressive cholesterol lowering has also been shown to yield larger decreases in the incidence of subsequent coronary events than angioplasty, and to reduce the occurrence of such events in patients who have undergone coronary artery bypass graft surgery, which raises the question of whether these procedures should be relegated to symptom relief, with cholesterol lowering as the primary means of coronary heart disease event prevention. Statins, therefore, have unequivocally shown the importance of cholesterol lowering in the prevention of morbidity and mortality due to coronary disease. Ongoing research will elucidate the role of statin therapy in the prevention of strokes and in the treatment of patients aged >75 years, and future trials will be needed to evaluate the potential role of statins in primary prevention for younger populations who cannot control cholesterol with lifestyle changes. (Am Heart J 2002;144:S21-6.)