Compensatory hyperhidrosis is a troublesome complication of thoracoscopic sympathectomy for hyperhidrosis. After extensive resection of the second through the fourth ganglion (T2-4), as well as after limited resection of the second ganglion (T2), the reported incidence of compensatory hyperhidrosis ranges as high as 50-97%. The purpose of this study was to determine whether the incidence of compensatory hyperhidrosis can be reduced by limiting the thoracoscopic sympathectomy to another level, the third ganglion.We analyzed 28 thoracoscopic sympathectomies for palmar and/or axillary hyperhidrosis. In all patients, the sympathetic chain was transected cranially and caudally to the third ganglion (T3 dissection). Long-term follow-up was conducted by interviewing patients using standardized questionnaires.The surgery was effective in all patients. After a median follow-up of 3.5 years, compensatory hyperhidrosis was not recorded in any of the patients. There were no recurrences of hyperhidrosis.Limited thoracoscopic sympathectomy at the level of the third ganglion is effective and seems to prevent compensatory hyperhidrosis.