The case histories of 32 patients treated in a University hospital for "minor causalgia during a recent ten-year period have been reviewed. The inciting causes were varied and could rarely be directly attributed to nerve injury. Patients with minor causalgia presented for treatment much later following injury than patients with "major" causalgia seen in the same hospital, and they exhibited varied physical signs. Osteoporosis was present in over half of the involved extremities examined radiographically. Because of the less severe nature of the pain, the remoteness of the injury, and the varied clinical presentation, over half of these patients had been treated unsuccessfully on the basis of other diagnoses and many were considered psychoneurotic. Sympathetic block proved to be the most accurate diagnostic aid and in four cases was of therapeutic benefit. Sympathectomy produced gratifying relief in 24 of 27 patients, and all patients who responded favorably to sympathetic block benefited from surgery. Follow-up in 15 patients, 2 to 17 years after surgery, revealed lasting relief in 13. In civilian practice, minor causalgia is more common than major causalgia, and, because it is so readily treated, early recognition is of great clinical significance.