Severe upper limb ischemia is uncommon, and patterns typical of lower limb ischemia are seldom seen. The conditions of 31 patients with actual or threatened gangrene or severe disability were evaluated from 1969 through 1978. Causes of ischemia included emboli, arteriosclerotic occlusions, trauma, thoracic outlet compression, and small-artery occlusions associated with Raynaud's phenomenon, rheumatoid arthritis, or scleroderma. Five patients had emboli from lesions in peripheral arteries, and two patients had ulnar artery occlusions. Twenty-three patients had operations with no deaths. There was one operative failure. Operative angiograms were used routinely. Patients with emboli from the heart received heparin sodium after operation. Sympathectomy improved the conditions of two patients with Raynaud's phenomenon and of one patient with ulnar artery occlusion. One third of the patients had significant arteriosclerotic lesions in other locations.