Total repair of tetralogy of Fallot was performed in 69 patients after the primary construction of a Blalock (28 patients) or a Waterston (41 patients) anastomosis. A total of 7 patients (10.1%) died. One to 5 yrs after correction, 62 patients (89.9%) survive: 52 (75.4%) are in a very good condition, 7 (10.1%) are in a good condition and the condition of 3 (4.4%) is unsatisfactory. 8 (11.6%) patients have serious late complications. The result of correction is not much influenced by the previous Blalock anastomosis (mortality rate 6.9%). After the Waterston anastomosis, however, there are frequent serious complications (pulmonary hypertension in 25.0% of patients), which adversely affect the result and increase mortality (12.5%) of the subsequent correction. The authors prefer two-stage repair of tetralogy of Fallot in the first two years of life. By administration of beta-blockers and prostaglandins they endeavour to postpone the construction of a Blalock anastomosis or an anastomosis performed by means of a polytetrafluoroethylene vascular prosthesis up to the age when the pulmonary artery branches are at least 4 mm in diameter. They plan the subsequent correction to be performed between the 2nd and the 5th year of age.