Transfusion of allogeneic blood products carry a small but not negligible risk for the transmission of infections and may have immunosuppressive or immunogenic effects. The discovery, licensing, and clinical use of hematopoietic cytokines such as erythropoietin or thrombopoietin may reduce the requirements for allogeneic blood transfusions. However, the effectiveness has so far only been demonstrated in limited clinical situations. Further progress in avoiding allogeneic transfusions can be expected from the development of artificial blood cell substitutes. The potential and limits of these new techniques and substances to manage pancytopenia in cancer patients are reviewed briefly. Copyright 2000 S. Karger GmbH, Freiburg