Blood transfusions prior to first cadaver kidney transplants have a significant beneficial effect on graft survival and, in this sense, appear to enhance the possibility of a compatible transplant. This desirable effect, however, occurs concomitantly with an increased degree of sensitization, which in turn reduces the likelihood of identifying a compatible kidney by direct crossmatch testing. This report illustrates that the beneficial effect is achieved with one to five transfusions prior to transplantation, but that more transfusions afford no additional benefits. In addition, the presence of cytotoxic antibodies per se does not have an adverse influence on graft survival. Liberal transfusion policies are therefore indicated in cadaver transplant candidates, but more than five transfusions prior to transplantation should probably be avoided unless clinically necessary.