Atherosclerotic vascular disease is the major cause of death and disability in adult men and women living in the United States, where 13-14 million adults have a history of coronary artery disease (CAD). One-third of the 1.5 million individuals who experience a myocardial infarction (MI) each year will die and one half of these deaths will occur within 60 minutes of the event. The relation between elevated serum lipids and CAD has been corroborated by epidemiologic as well as pathologic evidence. Approximately 96 million people have total cholesterol levels > 200 mg/dL, with 38 million of these individuals having values > 240 mg/ dL. The National Cholesterol Education Program (NCEP) identified elevated low-density lipoprotein (LDL) cholesterol as a primary risk factor for CAD in 1988. This conclusion, along with recommendations for assessment and treatment, was reaffirmed in 1993. The NCEP also recommended that high-risk patients, with or without clinical manifestations of coronary atherosclerosis, should substantially lower their serum cholesterol levels. Specifically, the NCEP recommends that patients with CAD need to maintain serum LDL cholesterol levels of < or = 100 mg/dL; this means that the vast majority of patients need to decrease LDL cholesterol levels by > or = 30%. Aggressive dietary and/or drug therapy are recommended to achieve these reductions. In recent years, clinical trials have demonstrated the efficacy of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors ("statins") in lowering elevated levels of LDL cholesterol and decreasing the risk for clinical coronary events.