Among 172 children who underwent repair of coarctation of the thoracic aorta from June 1, 1967, to June 1, 1979, there were 50 who were less than 6 weeks old. A review was undertaken to assess mortality and postoperative residual hypertension in this newborn age group. Forty-five (90%) had one or more associated congenital cardiac lesions, which were repaired or paliated at the time of coarctation repair. The three most common associated lesions were patent ductus arteriosus (74%), atrial septal defect (74%), and ventricular septal defect (62%). Thirty-one newborns underwent resection with parimary end-to-end repair with 8 deaths (26%), and 18 underwent Dacron patch angioplasty and 1 underwent subclavian angioplasty with 4 deaths (21%). Of the 38 survivors, 36 (95%) had good pedal pulses on postoperative clinical examination 3 months to eleven years postoperatively. Seventeen (45%) had upper and lower extremity blood pressure measured; 2 (5%) showed residual upper extremity hypertension (greater than 2 standard deviations above the mean and a gradient less than 20 mm Hg). One of these 2 patients has undergone repeat repair. Based on this low mortality and infrequent need for repeat repair, we advocate aggressive early operation and judicious use of palliative procedures in newborns, when indicated, for associated defects.