To determine which method of surgical therapy might be optimal for patients with anomalous left coronary artery from the pulmonary artery (ALCAPA), a follow-up study was performed. Twenty-nine teenagers and adults who had ALCAPA diagnosed during life at age 13 years or older were identified mainly by literature search. Recent follow-up was obtained on all. Thirteen treated by ALCAPA ligation alone (Group A), were followed a mean of 9.2 years postoperately (range 1 to 15 years). There was no operative mortality. Three Group A patients died suddenly; a mean of five years (range 2 to 7 years) postoperatively. Sixteen patients treated by simultaneous ALCAPA ligation and saphenous vein graft (SVG) from aorta to left coronary artery (Group B) were followed a mean of five years (range 0 to 11 years) with one intraoperative death and no late mortality. Using the generalized Wilcoxon test for single censored samples, there was no significant difference in survival at any postoperative year when comparing both Groups A and B. The late appearance of sudden death in three Group A patients and no late deaths in Group B patients suggests that ligation and SVG, or its equivalent, may be the therapy of choice.