In the past ten years the rapid expansion of private blood banks and the introduction of the Red Cross blood programs have made blood available in large quantities. With this marked increase in supply has come a much greater use on the part of physicians. In many hospitals transfusion care has passed from a rarity into a common form of therapy. Although there can be no doubt that this has brought about a great improvement in patient care, rapidity of convalescence and safety in surgery, an abuse has also crept in, in the form of administration of transfusions when no . . .