The HMG-CoA reductase inhibitors reduce levels of low-density lipoproteins, raise high-density lipoproteins, and lower triglycerides. Treatment with HMG-CoA reductase inhibitors reduces the risk of cardiovascular events across a broad spectrum of patient profiles, as evidenced by both primary and secondary prevention trials. Improved survival by way of reduced deaths from coronary heart disease was also reported with these agents, which are primarily indicated for substantial reduction in LDL-cholesterol levels. However, HMG-CoA reductase inhibitors are extremely complex drugs and exhibit a wide variety of vascular effects that may or may not be dependent on their lipid-modifying properties. These so-called pleiotropic effects include alternations of endothelial function, inflammation, coagulation and plaque stability. The relative contribution of the nonlipid effects of HMG-CoA reductase inhibitor therapy to the well-documented clinical benefits is currently under intense investigation.