Of 66 patients exhibiting Raynaud's phenomenon who have been followed from 1 to 25 years, 20 exhibited peripheral vascular disease, 35 were diagnosed as having collagen disease, 7 showed evidence of vasomotor hyperactivity, and 4 showed abnormal clumping of red blood cells or precipitation of globulin. Only 18 patients were subjected to bilateral dorsal sympathectomy. The failure rate is not so much due to the recurrence of sympathetic activity, but to case selection. Many patients have been erroneously subjected to sympathectomy, only to exhibit typical full-blown symptoms of scleroderma or lupus later. Results of the operations done in the presence of peripheral vascular disease, or because of a nervous discharge from the diencephalon, have been excellent except for 2 technical failures.