Over a period of 3 years, 21 infants under 3 months of age were operated upon for coarctation of the aorta by subclavian flap aortoplasty. Associated intracardiac defects were present in 13 patients (62%), VSD being the most frequently encountered (10 patients, 48%). In 8 patients coarctation of the aorta, with or without patent ductus arteriosus, was the only cardiovascular malformation. The indication for surgical treatment was intractable congestive heart failure despite intensive medical treatment. Eight patients were on mechanical ventilatory support prior to surgery. There was no early operative mortality. One patient died in congestive heart failure due to valvular aortic stenosis 3 months after surgery for correction of the coarctation. During a follow-up of from 2 months to 3 years, 5 patients underwent a second operation for correction of intracardiac defects. Nineteen of the surviving 20 patients are in good clinical condition. One patient has clinical evidence of residual coarctation; a blood pressure difference of more than 10 mmHg between right arm and leg is presented in 4 patients. Early subclavian flap aortoplasty is recommended for patients with coarctation of the aorta, with or without associated intracardiac defects, who remain in congestive heart failure despite medical therapy.