In 6 pairs of sibling Beagle dogs, 1 kidney was exchanged between pairs, and contralateral nephrectomy was done. Previously, one dog of each pair was given blood transfusions from the donor of its allograft. All dogs were given azathioprine and prednisone postoperatively for immunosuppression. Four of 6 dogs given pretransplantation transfusions were healthy 1 year after surgical manipulation was done, and 2 died for reasons other than graft rejection. Of the 6 dogs that were not given pretransplantation transfusions, 3 were healthy after 1 years, but 2 were euthanatized because of graft rejection, and the last was euthanatized because of both graft rejection and intussusception. Other complications in these dogs were leukopenia (7 dogs), interdigital abscesses (2 dogs), urinary infection (3 dogs), and renal vein thrombosis (1 dog). Considering the lack of alternative methods for effective therapy for chronic renal failure in dogs, results of this study seem encouraging for selective use of renal transplantation, clinically. This study supports previous reports which indicated that pretransplantation transfusion enhanced graft survival in dogs.