A 66-year-old woman with longstanding lichen sclerosus et atrophicus improved strikingly with PUVA bath photochemotherapy over a period of 6 weeks. The cumulative UVA dose was 31.7 J/cm2; the single UVA dose ranged from 0.3 to 2.3 J/cm2. After 16 treatment sessions, the sclerotic lesions had softened greatly, while after 24 treatments, the skin lesions were almost completely cleared and pruritus was diminished. Histopathological analysis of biopsy specimens from previously affected sites as well as 20 MHz ultrasound examinations showed almost no residual sclerosis. Although long-term results are not yet available, PUVA bath photochemotherapy seems to be a promising and effective new treatment modality without systemic side effects for patients with disseminated lichen sclerosus et atrophicus.