Radical prostatectomy (RP) remains the standard treatment for men with clinically localized prostate cancer, despite the range of alternative treatment modalities. Even with significant advances in surgical technique and superb results for cancer control and preservation of urinary function, erectile dysfunction (ED) following RP is a common complication. This is mainly attributed to temporary cavernous nerve damage (neuropraxia) resulting in penile hypoxia, smooth muscle apoptosis, fibrosis and veno-occlusive dysfunction. One of the most promising new approaches is the concept of early penile rehabilitation, which is thought to prevent ED after RP by countering post-RP pathophysiological changes during the period of neural recovery. Various treatments, such as vacuum constriction devices, intraurethral and intracorporal alprostadil, and phosphodiesterase type 5 (PDE5) inhibitors, might serve to facilitate recovery of erectile function. PDE5 inhibitors are considered as the first-line treatment for early penile rehabilitation, with superior erectile function outcomes compared to placebo. Definitive conclusions regarding the success of penile rehabilitation cannot be drawn at this time because of differences in study design, data acquisition, and definitions of potency. Continued prospective, rigorous study is needed to develop and bring forward this important field and to establish the best evidence basis for counseling and treating patients suffering from ED after RP.