A study of 24 children with lichen sclerosus et atrophicus (LSA) seen at the Mayo Clinic from 1940 through 1965 is reported. All the patients in the series were girls, the disease usually commencing before the age of 7 years. The anogenital region was affected most commonly, but 25% of the patients had extragenital lesions only. The effect of puberty, pregnancy, and anovular drugs is discussed.