Primary palmar hyperhidrosis is part of a triad of palmar, plantar, and axillary hyperhidrosis of unknown etiology, affecting children, adolescents, and young adults. Sixty-seven children and young adolescents were operated on during a 10-year period. A total of 103 transaxillary upper thoracic sympathectomies (36 bilateral) were performed, with no mortality. The immediate postoperative course was uneventful in 90%; the other 10% had mostly minor problems. The average hospitalization period was 3 to 4 days. Total abolition of palmar sweating was achieved in all but two patients in whom some residual moisture remained. Long-term extreme satisfaction was reported by 64 of 67 patients (94%). One was moderately satisfied, and two were not satisfied because of excessive "compensatory" sweating elsewhere. Compensatory sweating of some degree was reported by 45% of patients but did not alter satisfaction. By further limiting ganglionectomy to just one ganglion (T2 or T3), compensatory sweating possibly may be reduced further. Early surgery for severe palmar hyperhidrosis will save a child many years of agony and social discomfort because all types of conservative therapy are ineffective and cause unnecessary delay. A limited transaxillary upper thoracic sympathectomy is presently the authors' preferred approach, although ablation via thoracoscopy should not be excluded as further experience is gained with this modality.