Many case-control and cohort studies have identified a strong, independent and dose-related association between moderate hyperhomocyst(e)inemia and atherosclerotic vascular disease, with respect to the pathogenetic link between hyperhomocyst(e)inemia and stroke, the possible role in inducing an endothelial wall damage deserves special attention. Some prospective cohort studies have failed to demonstrate a positive association between elevated homocyst(e)ine (Hcy) levels and stroke. Further studies are needed, in order to better characterize the association between Hcy concentrations and risk of stroke.