The sacral region is one of the favorite sites for lichen (ruber) planus. Polygonal, purple papulo-plaques of variable size, often with itching, are typical. The same kind of lesions are regularly found in the extremities and often also in oral and/or genital mucous membranes. Potent topical corticosteroids form the basis of the therapy. In more severe cases also oral drugs (e.g. retinoids or cyclosporin-A) can be considered.