Ten of 357 patients (2.8%) who had total correction of tetralogy of Fallot in our institute between 1955 and 1983 required intracardiac reoperation. The indication for reoperation included residual lesions alone or in combination with other lesions. The reoperation consisted of a new patch closure of a residual ventricular septal defect in nine, reconstruction of a residual right ventricular outflow tract obstruction in five, repair of a left ventricle-right atrium communication in two, repair of tricuspid insufficiency in two and closure of an atrial septal defect in one. None of these ten patients had died at early or late follow-up periods (mean 5.3 years) or required further reoperation. A patient who has one or two of the following criteria, which are surgically correctable, and who would face deterioration in symptomatic status without surgical intervention is a candidate for reoperation: (1) Qp/Qs greater than 1.5, (2) Systolic pressure gradient between RV and PA greater than 50 mmHg, (3) Mean RA pressure greater than 20 mmHg, (4) CTR greater than 65%, (5) NYHA class III or IV.