Initially called the "X Syndrome" by Reaven, then the "Killer Quartet" by Kaplan, the MS prevalence has dramatically increased in the past decades. The first criteria elaborated by WHO in 1998, and afterwards reformulated in 1999, were conceived by diabetologists as a working instrument for clinical practice and they shall consequently be updated in accordance with the new acquisitions in this field. MS expresses the complex disorder of the organism energetic metabolism, having as central element insulin resistance and compensatory hyperinsulinism, associated with the presence of some risk factors involved in the etiology and/or physiology of atherosclerosis. The interaction between the genetic factors and the acquired ones induces a series of functional anomalies, which finally lead to a high risk of cardiovascular diseases. Abdominal obesity seems to be the most important component of the MS, which may be correlated with systemic inflammation and the decrease of adiponectin concentration. We should not overlook the part played by the other components: plasmatic TG, HDL, LDL - cholesterol, plasmatic glycaemia, blood pressure, microalbuminuria, plasmatic uric acid. The MS patient will be clinically and paraclinically examined by calculating the vascular and metabolic risks and, thus, establishing the therapeutical objectives and targets of every factor in order to maximally reduce the cardiovascular and DM risks. The treatment will be individualized, as present definitions include MS both in patients with clearly expressed diseases (Type 2 DM, Hypertension, coronary disease) as well as in patients with limit modifications. This fact will involve both improvement of lifestyle and drugs treatment, as well. MS prevention more and more imposes itself by individual and populational strategies of preventing obesity, through the educating population to adopt a healthy lifestyle, involving the whole medical staff.