Arterial insufficiency is the most common organic cause of impotence. The diagnosis can be established on a clinical basis through the use of Doppler probe evaluation of the penile pulses, penile blood pressure measuring, and nocturnal penile tumescence monitoring. The diagnosis may be confirmed by internal pudendal arteriography. Through microsurgical arterial revascularization, a 60 percent long-term success rate has been achieved. Two early and two late failures suggest the need for improved patient selection and confirm the progressive nature of the arteriosclerotic process.