Congenital long-segment intrathoracic tracheal stenosis (CTS) is a rare life-threatening obstruction in infancy and childhood. From July 1983 to March 1988 six infants aged 14 days to 14 months with CTS were identified. Symptoms ranged from recurrent stridor and wheezing to severe respiratory compromise and hypercarbia. Routine chest x-rays were not diagnostic. Definitive diagnosis was made by bronchoscopy, which showed complete tracheal rings in all patients with severely compromised tracheobronchial lumens. In three patients, pericardium was successfully used for anterior tracheoplasty with one early death due to fulminant sepsis in an infant with undiagnosed sickle cell disease. The other two died late, at 3 and 9 months from problems unrelated to the repair. In three patients a rib graft was used for repair; in one, tracheoplasty was required after earlier repair of tetralogy of Fallot. All are late survivors with no postoperative symptoms. After recognition of CTS, prompt surgery is warranted to avoid the late complications of tracheostomy for long-term ventilatory support. Rigid repair with rib cartilage is preferable to use of pericardium. Proper rib harvesting with intact perichondrium, intraoperative bronchoscopy, oxygenation by cardiopulmonary bypass, and meticulous graft alignment are necessary for successful postoperative outcome.