Lichen sclerosus (LS) is an inflammatory skin disease predominantly affecting the anogenital region. If untreated, progressive sclerosis results in scarring with distortion of the normal architecture. LS occurs more commonly in women than men but may occur in all age groups, including adolescents and prepubertal children. Its exact prevalence is unknown, but estimates range from 1:60 to 1:1000. In this article, LS is discussed in detail with respect to disease management in adults and children, risk of malignancy, and association with other diseases.