The late outcome in 226 patients who survived surgical repair of aortic coarctation was assessed 15-30 years after operation. Twenty six patients died during the follow up mainly from causes related to surgical repair or to associated cardiovascular anomalies. The survival rates of patients operated on between the ages of four and 20 years are 97%, 97%, 92% at 10, 20, and 30 years after operation. For patients operated on after the age of 20 the corresponding rates are 93%, 85%, and 68%. This difference is statistically significant from the fifteenth year of follow up onwards. The survival of patients operated on before the age of 20 is not significantly different from that of a comparable general Italian population. Recoarctation occurred in only 8% of patients who had end to end anastomosis, whereas it occurred in 35% of those who had other types of operation. Two thirds of the patients were hypertensive at the last visit. The actuarial curve shows that blood pressure was normal in most patients 5-10 years after operation, but 30 years after coarctation repair only 32% of patients are expected to be normotensive. Thus early repair of aortic coarctation appears to improve long term survival. Intervention in older patients and when blood pressure is high seem to be the most important predictors of late hypertension.