Twelve patient referrals for evaluation of impotence comprise the subjects of a pilot study examining psychogenic and biogenic factors of erectile dysfunction. A structured interview format (KCII) was developed which allowed the clinician to estimate the likelihood of the presence of three organic factors (hormonal, neurological, cardiovascular) and three psychogenic factors (intrapsychic, relational, and behavioral) as well as the presence of relevant lifestyle factors (alcohol, smoking, exercise patterns). The results demonstrated a good ability of the KCII to accurately identify impotent patients (on the basis of history) who would have positive or negative signs of hormonal factor or neurological factor confirmed by laboratory results or physical examination. The sample of patients who had significant vascular findings did not allow for adequate comparison with interview findings. The majority of patients had significant psychogenic components to their impotence and might have been incorrectly classified as "solely psychogenic" if they had not been simultaneously evaluated for organic factors. The most important finding was that impotence, in most cases, involved multifactorial etiological components and required a comprehensive evaluation and treatment program.