Auxiliary liver allotransplantation1 has advantages not yet realized in practice. In patients with portal hypertension and extensive venous collaterals, heterotopic transplantation would doubtless carry a lower morbidity and mortality than hepatectomy and orthotopic transplantation. The diversion of portal blood necessary to prevent atrophy of either a normal or a transplanted liver2-8 should not be harmful in patients undergoing auxiliary transplantation, because they would already have severely impaired liver function. Further-more, the surgeon would have the alternative of removing the auxiliary liver and replacing it with another allograft if rejection occurs. We present here a method of auxiliary partial liver transplantation that provides for complete diversion of portal blood flow (portalization) through the graft. Like the method suggested by Price5 and Mito6 and their colleagues, it provides also for transplantation of only part of the liver in order both to allow the auxiliary transplant to fit easily