Low density lipoproteins (LDL) size seems to be an important predictor of cardiovascular events and progression of coronary artery disease and the predominance of small dense LDL has been accepted as an emerging cardiovascular risk factors by the National Cholesterol Education Program Adult Treatment Panel III. We recently showed increased LDL size or higher levels of small and dense LDL in different categories of patients at higher cardiovascular risk, such as those with coronary (including acute myocardial infarction) and non-coronary (including carotid disease, abdominal aortic aneurysm and peripheral arterial disease) forms of atherosclerosis or metabolic diseases (including type-II diabetes, polycystic ovary syndrome, growth hormone deficiency, gestational diabetes and the metabolic syndrome). Screening for the presence of small, dense LDL may potentially identify those with even higher risks and may contribute in directing specific treatments in order to prevent new cardiovascular events. This seems particularly true for statins and fibrates. Promising data are available for rosuvastatin, the latest statin molecule introduced in the market, and ezetimibe, a cholesterol absorption inhibitor.