We report our initial experience, over the past 3 years, with thoracoscopic sympathectomy for severe, primary, palmar hyperhidrosis in children and adolescents. From 1992-1995, 179 thoracoscopic sympathectomies were performed in 61 girls and 35 boys, 5.5 to 18 years old (mean 14.8). During the first 2 years the procedures were performed bilaterally but not simultaneously. During the past years, 65 underwent bilateral, simultaneous sympathectomy, using a single 10 mm subaxillary port of entry. 94 (98%) had immediate and permanent relief of palmar sweating. The immediate postoperative course was uneventful in all except 2 who had residual pneumothorax that required 24-hour intercostal drainage. These results compare favorably with the open method and are actually better in terms of less pain, early discharge, quicker return to normal activity and a smaller and less conspicuous scar. We emphasize the benefits of early surgery in children with severe, palmer hyperhidrosis, to avoid the many years of psychological, social and physical discomfort during adolescent growth and development.