A Bulgarian team, within the frames of a multinational study on diabetic vascular disease, sponsored by WHO, studied a group of 473 diabetic patients by the inquiry method and by the determination of blood cholesterin and creatinine and urine albumin. The results were compared with those of the whole group (6695 patients from 14 countries) and with each national group separately. A higher percentage of insulin-treated patients was established in the Bulgarian group as compared with the whole group, fewer hypertonics, lower mean cholesterol values, a little higher average body weight and considerably lower percentages of smokers. The various forms of macroangiopathy among the Bulgarian group proved to be in percentages, approaching the average percentages for the whole group or little lower than them (e.g. for the category "probable infarctions" and "cerebral hemorrhages"). Only for the category "IHD" the affection percentage among the Bulgarian group significantly surpassed that of the whole group. Since the Bulgarian group, as regards the possible risk factors, is in a more favourable condition, the higher IHD percentage is admitted to be due to the circumstances that patients with graver states have been included in the group. That is suggested by the higher percentage of patients (52%), insulin-treated. The severity of diabetes is concluded to be a significant factor in the development of macroangiopathy.