Erectile dysfunction is a known and much-dreaded functional consequence of radical prostatectomy. Dr. Patrick Walsh pioneered the nerve-sparing radical retropubic prostatectomy in the early 1980s, which has mitigated the morbidity of this surgery. Postoperative potency rates range widely from 20 to 80%, however, and depend on myriad factors including age, preoperative potency, and degree of nerve-sparing during surgery. Over the past four decades several developments have continued to offer hope to patients and clinicians alike, including refined understanding of cavernosal nerve neuroanatomy, beneficial modifications in surgical technique, as well as the advent of robotic surgery. Furthermore, multiple pre-and post-operative penile rehabilitation techniques using mechanotherapy and pharmaceuticals have also improved functional recovery. This paper examines erectile dysfunction as a consequence of radical prostatectomy, including the physiology of erections, the pathophysiology of post-operative erectile dysfunction, novel surgical techniques to enhance neurovascular bundle preservation, and penile rehabilitation strategies involving hyperbaric oxygen, neuroprotective pharmaceuticals, dehydrated human amnion-chorion membrane allografts, and mesenchymal stem cell therapy.