To evaluate the immediate and long term results of complete correction of tetralogy of Fallot (TF), we have reviewed the records of 275 children operated on in Geneva between 1972 and end 1984. The average age at operation was 6 7/12 years (range 7 months to 16 years). Postoperative follow-up ranged from 1 year to 12 years (average 3 7/12 years). The survival rate, taking into account immediate postoperative mortality, was 90 +/- 2% after one year, 88 +/- 2% after 5 years and 88 +/- 2% after 11 years for the entire patient group. The total mortality of 9.8% has markedly decreased in recent years (14.5% before and 5.7% after 1978). Mortality is highest within the first 30 days after the operation (20 cases, 7.3%). Mortality was higher after previous palliative surgery (5/51) and for children who had to be reoperated for a residual lesion (4/23). Once the first postoperative year has passed, mortality is low: 2 deaths occurred between 1 and 2 years, and one between 2 and 5 years after the operation. Cardiac catheterization in 218 patients between 2 months and one year after surgery showed severe residual pulmonary stenosis in 4 children which made reoperation necessary; a second operation was needed for a large left-to-right shunt in 5 cases, and because of a ventricular septal defect with residual pulmonary stenosis in 6 others. Pulmonary insufficiency was noted in 106 cases (38.5%) but only 3 children showed right heart insufficiency. One child underwent pulmonary valve replacement by Björk-Shiley prosthesis. It can be concluded that a child with surgically treated TF has excellent long term survival, and that life threatening complications after the first postoperative year are rare.