Progressive advances in perfusion technology and perioperative supportive management have made it possible for members of the Jehovah's Witnesses religious group to undergo open cardiac operations with remarkable safety. However, hospital mortality remains high in (1) patients requiring reoperation (in whom both technical and bleeding problems tend to be more frequent) and (2) patients with significantly compromised cardiac performance requiring urgent or emergency operation. Employing a number of perioperative measures designed to minimize blood loss and maintain hematocrit levels (including use of the recently available recombinant human erythropoietin in two patients whose cases are reported herein), 13 reoperations and five urgent or emergency operations were performed. The one death in the entire series occurred in a patient (reoperation group) who died of a cerebrovascular accident of presumed embolic etiology, having undergone combined debridement of a stenotic heavily calcified aortic valve and a second coronary artery revascularization procedure. None of the patients required surgical exploration for bleeding. We suggest that currently available methodology permits Jehovah's Witnesses to undergo reoperation, emergency surgery, or urgent open cardiac operation at a level of risk not dissimilar to that seen in patients who permit use of homologous blood and products in their treatment.