We recently established a multidisciplinary center for the evaluation and treatment of male sexual dysfunction. The patients are seen in a single day by the endocrinologist, psychiatrist, psychologist, neurophysiologist and urologist. Laboratory studies include chemical and hormonal profiles, pudendal nerve latency testing and determination of the penile blood pressure. Nocturnal penile tumescence studies are done in selected cases. A diagnosis was made in 95 of 106 patients (90 per cent). The problem was psychogenic in 42 per cent of the patients, vascular and neurologic in 34 per cent, hormonal in 15 per cent, urologic in 7 per cent and medication-related in 2 per cent. The interdisciplinary approach to this problem allows for a more comprehensive and accurate evaluation, while providing a convenient service to the patient.