Adequate sexual expression is an essential part of many human relationships, and may enhance quality of life and provide a sense of physical, psychological and social well-being. Epidemiological and clinical studies show that depression is associated with impairments of sexual function and satisfaction, even in untreated patients. Most antidepressant drugs have adverse effects on sexual function, but accurate identification of the incidence of treatment-emergent dysfunction has proved troublesome, as disturbances of the sexual response can only be detected in a reliable fashion when systematic enquiries are made before and during the course of treatment. Growing awareness of the adverse effects of many antidepressants on sexual function has led to attempts to resolve dysfunction though adjuvant or substitution treatment approaches. There is a need for further studies of the effects of antidepressants on sexual function.