1. Eighteen men who complained of impotence and who had no obvious disease of the central nervous system, no marked structural changes in the genito-urinary tract except for absence of spermatozoa in Case 4, or no manifest deficiency in the internal secretion of the testes, were given intramuscular injections of testosterone propionate in 25 mgm. doses three times or more weekly.2. In some of our patients psychic and emotional influences played a large part in the production of the impotence.3. In seven instances relief from the impotence was obtained, while in the eleven other subjects the testosterone propionate did not produce any beneficial effects.4. In one patient there was a definite reduction in the number of spermatozoa during the course of treatment.5. It was concluded that the successful results were probably explained by psychological factors, since there was no decrease in potency when sesame oil was substituted and when all injections were stopped.6. The amount of androgens administered by us was thought to be sufficient to make up for deficiency in testicular secretion. It is, however, desirable to secure experience with larger amounts of the agent.7. It is our opinion that the depth and degree of neurotic conflicts present in the individual patient may play an important rôle in determining the nature of the results. We suggest that beneficial effects may be observed in those patients in whom neurotic trends are minimal, and who react to such physiological stimulation as testosterone propionate may induce by enough increase in self-confidence to overcome the impotence. We suggest, furthermore, that failure may be noted in those patients who have severe neuroses, and whose conflicts are so enhanced by the physiological stimulation that the anxieties and fears thus aroused lead to still further inhibition of sexual expression. But it should not be forgotten that testosterone propionate may have had no influence whatsoever on sexual excitability, as seems to be the case in normal men, and such benefit as we have observed may be due only to suggestion.