Between 1967 and 1976, 106 children with transposition of the great arteries (TGA) (55 simple, 51 complex) survived the Mustard procedure. Late death occurred in 8 patients (1 simple, 7 complex TGA). Cardiac arrhythmia developed in 31 patients, 6 of whom required a permanent pacemaker. Postoperative cardiac catheterization showed mild superior vena cava obstruction in 4 patients, mild pulmonary venous obstruction in 3, and baffle leak in 4. Only 1 of these patients underwent reoperation elsewhere for a baffle leak. Two other patients had reoperation for subpulmonary stenosis and 1, for tricuspid regurgitation. The actuarial survival at 18 years is 92 +/- 2.3%, and the event-free survival is 83 +/- 3.8% (95% confidence limits). Eighty-seven patients are in New York Heart Association Functional Class I, and 3 are in Class II. The results of this study show that the long-term survival and event-free survival have been satisfactory. Late death was significantly higher in patients with complex TGA (p = .027). Postoperative arrhythmia was common, but only 6 patients required permanent pacemakers and the incidence of late complications and reoperation has been low.