A healthy 44-year-old woman presented with a 1month history of diffuse arthralgias followed by skin discoloration of the fingers of both hands that progressed during a 1-week period and was accompanied by resting finger pain exacerbated by exposure to cold. She had a 25-pack-year history of cigarette smoking but no history of illicit drug use. Results of an Allen test were abnormal. Angiography revealed normal vessels interspersed with severe occlusive disease. Work-up with echocardiography and serologic testing for autoimmune antibodies, thrombophilia, and vasculitides, including anticentromere and anti-Scl-70 antibodies, yielded negative results. Thromboangiitis obliterans (Buerger disease) was diagnosed. Thromboangiitis obliterans is a nonatherosclerotic inflammatory disorder of unknown etiology that affects small and medium-sized vessels of the extremities and has a strong association with smoking. Angiographic findings may mimic those of conditions such as scleroderma (CREST syndrome) or prothrombotic disorders. Cessation of cigarette smoking is the only known effective therapy. This patient quit smoking and was treated with aspirin, dalteparin, and daily arterial flow pump therapy, which produced symptomatic improvement.