We examined the need for intervention after coarctation repair in a retrospective study of 197 procedures performed between 1967 and 1989. Reintervention was required in 23 patients. No technique of coarctation repair was free from complications. Although there were only two stenoses in the group receiving Dacron patch angioplasty, only seven of these procedures were performed in children under the age of 1 year. The risk of stenosis was inversely correlated to the age at primary repair, with children less than 1 year old being at greater risk than those more than 1 year of age (p less than 0.05). Subclavian flap angioplasty had a lower risk of reoperation than end-to-end anastomosis (p less than 0.02). Formation of true aneurysms was confined to the Dacron patch angioplasty group. The morbidity and mortality for reintervention was low in all groups, with only one procedure-related death and no incidence of paraplegia. Although no technique is free from risk, subclavian flap angioplasty leads to fewer reinterventions in younger patients.