Clinical trials have unequivocally demonstrated that lowering levels of low-density lipoprotein cholesterol with statins prevents cardiovascular events. As a result, statins have become an integral component of therapeutic strategies to reduce cardiovascular risk. A number of important issues remain to be defined with regard to the optimal use of statin therapy in clinical practice. In particular, the ideal does, when to initiate therapy in relation to an acute ischemic event, and the duration of treatment remain uncertain. Results from a number of recently reported trials that investigate the impact of statin therapy on atherosclerotic plaque and clinical events provide further clarification with regard to these issues.