The management of erectile impotence in renal transplant patients remains problematical. The enhanced risk of surgical infection in this immunosuppressed patient population must be addressed if prosthetic implantation is contemplated. A case of Fournier's gangrene (synergistic necrotizing gangrene of the genitalia) following implantation of a Small-Carrion penile prosthesis is reported. This potentially life-threatening infection demonstrates graphically the surgical infection risk of this population and suggests extreme caution before proceeding with a prosthetic operation in this unique subset of impotent patients.