Erectile dysfunction (ED) is a common medical condition linked both to aging and to many medical conditions such as diabetes mellitus and cardiovascular disease. Although a common condition, treatment for ED has in the past been conducted by a few specialists, mostly urologists and sex therapists. The revolutionary introduction of oral therapy, and the massive amount of research into sexual dysfunction that followed, has led to paradigm shift in the treatment of ED. This is no longer something done by a few for a few; it involves all disciplines of medicine and more patients are being treated by a greater number of physicians. Several medications administered by different routes are available for treating ED but oral pharmacotherapy represents the first-line option. Phosphodiesterase (PDE) type 5 inhibitors are the most widely prescribed oral agents and they have a satisfactory efficacy-safety profile in patients of all categories. An alternative for men who do not respond to PDE5 inhibitors is intracavernosal injection therapy with alprostadil, a prostaglandin analogue. Other alternatives include sublingual apomorphine and intraurethral alprostadil. Both agents have a less satisfactory efficacy profile than PDE5 inhibitors and a low compliance rate. The aim of ED treatment is to restore an erection satisfactory for the sexual needs of the patient. Thus, the patient-reported outcome is the gold standard in efficacy evaluation. There are now three PDE inhibitors available, all with satisfactory efficacy-safety profiles, but with different pharmacokinetic properties. The availability of three different agents has initiated studies aiming to evaluate them regarding patient preference. However, the results are rather conflicting with some studies suggesting that tadalafil has the best patient preference, while others fail to demonstrate a clinically significant difference between the three agents. However, there is a tendency for younger men to choose tadalafil because it gives them a broader window of opportunity, while older men tend to prefer vardenafil or sildenafil. These data could be used when making a decision on which PDE5 inhibitor to prescribe, although another option is to let the patient try all three available agents and make his own choice.