Sex is an important part of life. For many men, thinking about sex starts early, often before puberty, and lasts until their final days on earth. On one level, sex is just another hormone-driven bodily function designed to perpetuate the species. On another, it's a pleasurable activity. It's also an activity that can help cement the bonds between two people. Sexual health refers to a state of well-being that lets a man fully participate in and enjoy sexual activity. A range of physical, psychological, interpersonal, and social factors influence a man's sexual health.

Optimal male sexual health includes sexual desire (libido) and the ability to get and sustain an erection (erectile function). Although physiology can affect both the desire for sex and the ability to have sex, mental health and emotional factors also play important roles. Male sexual health isn't merely the absence of disease. Erectile dysfunction (ED) is the inability to get an erection or to maintain it long enough for satisfying sexual activity. Many things can cause ED, including stress, depression, relationship issues, abnormally low testosterone, damage from urological surgery, and even cholesterol-clogged arteries. In fact, it is often an early warning sign for heart disease. ED can be treated with pills, injections into the penis, or devices.  Men can also experience difficulties related to ejaculation, including premature ejaculation, delayed ejaculation, or the inability to experience orgasm upon ejaculation (anorgasmia). Male sexual health also covers the prevention and treatment of sexually transmitted diseases and the assessment and treatment of male infertility.