Purpose and Approach To report a case of morphea (localized scleroderma) in a patient following breast cancer therapy and to summarize the current literature. Results and Conclusion The occurrence of morphea is an unexpected late effect (approximately 1 year after the end of radiation therapy) which occurs frequently in the irradiated breast in women with breast-conserving therapy. The pathogenesis is unclear. The main differential diagnoses are recurrence of carcinoma and a radiogenic subcutaneous fibrosis (in most cases, the final diagnosis can only be made by means of a biopsy). Diagnosis and therapy must be performed in cooperation between dermatologist and radiooncologist.