Some three decades after bone marrow transplantation was introduced in the field of hematology and oncology, transplantation today continues to rapidly grow and expand into a variety of new modalities. Peripheral blood has been established as an effective source of autologous progenitor cells. Furthermore, the graft-versus-leukemia effect has resulted in novel strategies of adoptive immunotherapy for cancer. Finally, approaches to gene transfer and therapy are utilizing transplantation methodologies and can augment their effects. Current results, new developments and perspectives are presented in this volume. Conventional and innovative experimental approaches, the past and the future of bone marrow transplantation are reviewed and discussed by leading representatives.