The epidemiology of diabetic nephropathy (DN) should be approached from two angles: a) incidence of diabetic nephropathy in patients with diabetes, and b) epidemiology of chronic renal failure (CHRF) in diabetic patients. According to data from different sources, DN affects, in all its stages, about one third of patients irrespective of the type of diabetes they suffer from, with the peak rate of incidence after 15 years of duration of the illness.