Thirty-eight episodes of culture-documented antibiotic-resistant bacterial or fungal infection in patients with malignant neoplasms were treated with daily granulocyte transfusions until the infection improved or the patient died. Cumulative summation temperature plotting allowed easier interpretation of recipient fever response. Seventy-one percent of recipients had a favorable response to transfusion. There was no difference in mortality between patients treated with cells collected by filtration (FL) or intermittent flow centrifugation (IFCL) leukapheresis techniques. Transfusion reactions were more than twice as common with FL than IFCL collected cells. Seventy-four percent of recipients were alive 21 days after completion of transfusions; of the ten deaths, five could be classified as granulocyte transfusion failures. This study suggests that long-term granulocyte transfusion may be required in infected recipients when autologous granulocytes do not return after chemotherapy.