Between 1977 and 1986, 3,500 patients were examined for the symptom of impotence; 1,250 of them received multidisciplinary investigation permitting the diagnosis of a pure organic or mixed disorder in 85% of cases, including 62% of vascular disease subdivided into arterial (40%) and venous (22%). For 1,062 patients, 1 or several of the following therapies were used: intracavernous infusion of vasoactive drugs (N = 725), auto-injections (N = 235), vascular surgery (N = 357) and prostheses (N = 23). The diagnostic approach, formerly analytical and making use of multiple non-invasive methods, such as nocturnal erection plethysmography (NPT) and invasive methods (artificial erection, arteriography) have been transformed by the use of pharmacological tests associated with visual sexual stimulation (VSS) which enable, together with Doppler velocimetric examination, simple screening of vascular impotence based on the study of 4 parameters: penile pressure index (PPI) when less than 0.91 is always a sign of an arterial problem, the severity of which is directly proportional to the lowering of this index and the association with maintenance insufficiency; the initial intracavernous flow rate (IICF) depends overall on the maintenance flow and the state of erectile tissue, resulting from pharmacological stimulation by a low dose of papaverine (8 mg); penile rigidity attained by the combined action of pharmacological and visual sexual stimulation, reflecting the functional erectile capacity; the duration of the rigidity thus obtained on stoppage of VSS indicating the capacity for maintenance of erection. In the event of suspicion of an isolated venous leak or in association with arterial problems, it is the artificial erection with cavernosography, carried out after pharmacological stimulation, which enables the severity of the leak to be assessed. The following specific investigations are carried out to investigate a specific associated etiology: electromyogram for neurological disorders, hormone assay for endocrine disorders and psychological study using the MMPI questionnaire (Multiphasic Minnesota Personality Inventory). One can thus distinguish several groups of patients suffering from vascular impotence depending on the degree of arterial involvement: minor (PPI between 0.75 and 0.9), moderate (PPI between 0.65 and 0.75) and severe (PPI less than 0.65); depending on the degree of venous leaking: absent (MI less than 0.3 and/or MF less than 25 ml/min), minor (MI between 0.3 and 0.5 and MF between 30 and 50 ml/min), moderate (MI between 0.5 and 75 ml/min) and severe (MI greater than 0.75 and/or MF greater than 75 ml/mn).(ABSTRACT TRUNCATED AT 400 WORDS)