We treated 138 patients with severe Peyronie's disease by insertion of an inflatable penile prosthesis and manual modeling of the erect penis. This novel technique was successful in 118 patients (86%) in achieving a straight, rigid erection. In 11 patients (8%) penile modeling did not result in satisfactory straightening and relaxing plaque incisions were performed. Complications of penile modeling included urethral perforation in 4 patients (3%). Infection of the prosthesis occurred postoperatively in 4 patients (3%). At a mean followup of 32 months (range 9 to 84) 124 patients (90%) were actually using the penile prostheses and none reported penile shortening or impairment of glandular sensation. We suggest that penile modeling over an inflatable penile prosthesis is an important new technique for the patient with severe Peyronie's disease.