Objective To assess the effectiveness of a progressive local treatment protocol for erectile dysfunction (ED) in patients after undergoing radical retropubic prostatectomy (RRP) for prostate cancer. Patients and Methods The study included 85 patients (mean age 59.5 years, range 50-75) with ED after RRP. Treatment was offered in four progressive phases, with patients passing to the next phase only if they failed the previous one: in phase I patients used a vacuum erection device; in phase II, sildenafil; in phase III, intracorporal injection; and in phase IV, intracorporal injection plus the vacuum erection device. The patients were followed for 1 year. Results Of the 85 patients, 78 (92%) responded to the vacuum erection device (with an erection sufficient for vaginal penetration), but only 11 (14%) agreed to continue with it at home. Of the remaining 74 patients, 69 with no contraindications were given sildenafil and 14 (20%) had a positive response. Sixty patients were then treated with intracorporal injection and 51 (85%) had a positive response; four of the nine failures in phase iii responded to intracorporal injection plus vacuum therapy. Five patients failed all four protocols. After I year of follow-up, 76 of the 80 patients were successfully continuing treatment at home: seven (9%) used the vacuum erection device, 11(14%) sildenafil, 54 (71%) intracorporal injection and four (5%) intracorporal injection plus the vacuum erection device. Conclusion Overall, this progressive treatment method gave a positive response in 80 of the 85 patients (94%). After 1 year of follow-up, 76 of the 80 patients (95%) continued to respond well. Of all the methods used, intracorporal injection was the most effective for ED after RRP.