Autologous bone marrow transplantation (BMT) has become effective therapy for high-risk hematologic leukemias with long-term disease-free survivals and apparent cure in a substantial fraction of patients with relapsed aggressive non-Hodgkin's lymphoma, relapsed Hodgkin's disease, and the acute leukemias. Preliminary reports suggest autologous BMT may also be useful treatment for low-grade non-Hodgkin's lymphomas, chronic myelogenous leukemia, and multiple myeloma. Recent studies have begun to address the role autologous BMT should play in these diseases, especially relative to conventional-dose therapy and allogeneic BMT. Relapse remains the major cause for failure following autologous BMT. Novel approaches that can increase the antitumor effect of this treatment without increasing toxicity are being investigated.