Infection remains a major cause of death in patients receiving chemotherapy for malignant diseases. One approach to the problem of septicemia and high mortality in these patients was the therapeutic use of granulocyte transfusions. Improvements in collection techniques, employing continuous flow centrifugation, permitted the collection of granulocytes from a single, normal donor in sufficient numbers to study their application in the treatment of infections in granulocytopenic patients. Studies had demonstrated the efficacy of granulocyte transfusions as an adjunct in the therapy of septicemia due to gram negative microorganisms associated with granulocytopenia.