Upper extremity arterial disease is much less common than lower extremity involvement and typically presents as arm claudication, Raynaud's syndrome, rest pain, ischemic ulcerations, or gangrene. The disease can reflect an underlying systemic disorder. In addition to clinical examination, diagnostic studies include noninvasive vascular studies, serologic, immunologic, and hematologic studies (when indicated), and selective arteriography. Atherosclerotic disease is the most common cause of large vessel obstruction, but it can also cause small vessel obstruction by atheromatous embolization or thromboembolism. Treatment varies from pharmacological therapy for vasospastic and vasculitic syndromes to operative approaches for endarterectomy or bypass of focal lesions. Angioplasty and stent techniques also can provide an effective treatment option.