Pyoderma gangrenosum is a painful, noninfectious, ulcerating skin disorder often associated with systemic disease. Thalidomide has been used to treat many inflammatory dermatologic conditions and has been reintroduced in the United States to treat immune-modulated diseases such as pyoderma gangrenosum. The patient described, a 47-year-old man, had histologically confirmed pyoderma gangrenosum that did not respond to treatment with several courses of methylprednisolone. The ulcer healed with 10 weeks of oral thalidomide administration.