Erectile dysfunction (ED) is an inability to attain or maintain an erection sufficient for satisfactory sexual intercourse. It is an undertreated and underdiagnosed condition that can be due to vasculogenic, neurogenic, hormonal and psychogenic factors. Effective treatment of ED should restore quality of life and allow patients to return to the sex life they had before. Current therapeutic options include non-pharmacological treatments, locally administered drugs and oral therapies. The oral phosphodiesterase-5 (PDE5) inhibitors are considered first-line treatments of ED and have revolutionized ED management in the last five years. Three PDE5 inhibitors are currently available, sildenafil, vardenafil and tadalafil. They are all effective with similar efficacy and good safety profiles. However, tadalafil has the added benefit of a broad window opportunity offering patients more freedom to choose when to initiate sexual activity.