In the past several years, a substantial amount of new information on the epidemiology and pathophysiology of diabetes and vascular disease has become available. Autopsy studies suggest that diabetic patients are susceptible to cerebral small-artery disease and lacunar infarction and may be at risk for large-artery atherosclerotic occlusive disease. Epidemiological studies show that diabetes is a risk factor for ischemic stroke. The pathogenesis of diabetes-associated stroke appears to be linked to excessive glycation and oxidation, endothelial dysfunction, increased platelet aggregation, impaired fibrinolysis and insulin resistance. Macrovascular complications may be prevented by simple primary prevention measures including exercise, weight loss and treatment of dyslipidemia. The role of tight glycemic control in reducing the risk of stroke is still uncertain. Many new insights and treatment strategies are expected in the future.