In patients with arteriosclerosis obliterans of the lower limbs immediate (operative risk) and long term prognosis depend on the diffusion of the atheroma to other arterial beds (coronary and carotid). Basic investigations were completed by doppler ultrasonography of the cervical arteries, exercise electrocardiogram and lateral aortogram. Doppler ultrasonography revealed significant degrees of stenosis of the cervical arteries in 67 out of 402 patients (16.6 p. 100). The stenosis were totally latent clinically in 13 patients. Valid results were obtained in 72 p. 100 of 140 after an exercise electrocardiogram. It was positive in 19 p. 100 of patients without clinical or electric sign of coronary heart disease. Lateral aortogram in 125 patients showed atheromatous lesions in 39 cases (31 p.cent). These were often multiple and involved the coeliac and superior mesenteric arteries in 13 cases. These investigations are of great importance in making the therapeutic decision, indications related with risk and resulting priorities. Alarming coronary or carotid lesions may indeed require treatment before arterial disease of the lower limbs.