It is our belief that lichen sclerosus et atrophicus, which has often been designated "lichen planus sclerosus et atrophicus" (Hallopeau1), "lichen planus morphoeicus" (Crocker2) or "white spot disease" (Johnston and Sherwell3) in the German literature, is a distinct entity and can be distinguished both clinically and pathologically from atrophic forms of lichen planus on the one hand and from localized forms of scleroderma, including morphoea guttata, on the other hand. We urge the abandonment of the term "white spot disease," which has been loosely employed in different countries and by different authors to designate both lichen sclerosus4 and morphoea guttata.4a The present study is based on a review of 46 cases of lichen sclerosus et atrophicus. In 19 the diagnosis was confirmed by removal of a specimen of skin for biopsy. Distinction was made between lichen sclerosus et atrophicus and various forms of localized scleroderma,