The role of the hypocholesterolemic therapy in reinfarction prevention is evaluated using data from observational and secondary prevention studies. Even though survival after myocardial infarction is largely determined by the extension of the necrotic lesion, hypercholesterolemia remains an important risk factor for new vascular events. A total cholesterol reduction < 200 mg/dL (or even better LDL cholesterol < 100 mg/dL) in these patients is associated within few years with a significant reduction of both clinical events and total mortality. The reduction of clinical events is obtained in a relatively short period of time thus suggesting that plasma cholesterol reduction induces quite rapidly some modifications of the natural history of the atherosclerotic plaques, this effect being more relevant in vulnerable or unstable lesions that are responsible for most of the clinical events. These observations show that after myocardial infarction it is useful to reduce cholesterol < 200 mg/dL also with the use of drugs.