One hundred and twenty patients with transposition of the great arteries (TGA) were encountered over a decade. Survivors have been followed until after definitive repair, and 39% were alive when reviewed.The majority (69%) had no significant communication between the pulmonary and systemic circulations. Of 48 patients in this poor-mixing group who had an atrial septectomy, 23 (48%) survived to have an atrial baffle repair at an average age of 37 months, and 37% were alive at the time of review. In contrast, 18 of 22 (82%) patients with poor mixing who had a balloon septostomy had a definitive operation at an average age of 13 months, and 17 (77%) survived.Twenty patients (17%) had good mixing between the two circulations due to the presence of a large ventricular septal defect (VSD) or patent ductus arteriosus, and presented with mild cyanosis and heart failure. Of this group, 35% were alive when reviewed. Four of the five patients who had a successful atrial baffle repair and correction of associated lesions were less than 4 months of age when this was performed. Where TGA was associated with VSD and pulmonary stenosis, 36% survived.Definitive operation at an early age has been made possible by the introduction of a surgical technic using profound surface-induced hypothermia and limited cardiopulmonary bypass.