The excellent results of coronary artery bypass with the internal mammary artery and the increasing numbers of patients who need coronary reoperations, but for whom conventional bypass conduits are not available, have prompted us to evaluate alternative arterial bypass conduits. The right gastroepiploic artery has been used as a coronary bypass graft in 36 patients (32 men), whose ages ranged from 29 to 71 years. Twenty-two patients had had previous coronary bypass grafting and six of these were undergoing their third bypass operation. The right gastroepiploic artery was used as an in situ graft to the right coronary artery or circumflex branches for 17 patients and as an aorta-coronary ("free") graft in 19 patients, six to the left anterior descending or diagonal, six to the circumflex, and seven to the right coronary artery. In conjunction with right gastroepiploic artery grafting, 16 patients received bilateral internal mammary artery grafts and 17 received one internal mammary artery graft. Histologically, right gastroepiploic artery segments from 18 patients could not be distinguished from internal mammary artery segments, and no evidence of atherosclerosis was found. Two patients died in the hospital, one intraoperatively and one 3 months after the operation, of a perioperative stroke. Perioperative morbidity included wound complication in three and reexploration for bleeding in two. At late follow-up 1 to 38 months after operation, two late deaths had occurred and 21 patients were free of symptoms. Postoperative angiography (postoperative interval 1 week to 13 months) was performed in nine grafts, three in situ grafts to the right coronary artery and six free grafts that included two to the left anterior descending, three to the circumflex, and one to the right coronary artery. All right gastroepiploic artery grafts were patient. The right gastroepiploic artery is an arterial conduit that can be used as an in situ graft to posterior coronary vessels and as a free graft to any coronary arterial system. Early graft patency has been excellent, and the histologic similarity between the right gastroepiploic artery and the internal mammary artery suggest that the long-term results will be favorable.