The use of intensive therapy together with transplantation of marrow from a suitable donor is the only established curative treatment for patients with chronic myeloid leukemia (CML). However, marrow transplantation is hazardous, costly and applicable to relatively few patients. Therefore, we evaluated the results and limitations of marrow transplantation for CML and discussed new treatment strategies. We decided to select a limited number of papers that focused on the relevant issues rather than to undertake an exhaustive comparison of treatment results from different centres. Patients with CML in the chronic phase who receive marrow from a sibling with the same human leukocyte antigen type can expect to have a long-term disease-free survival rate of 50%. However, the procedure is associated with a mortality rate of 30%, mainly because of graft-versus-host disease (GVHD) and interstitial pneumonitis. Moreover, because of the requirements for age and histocompatibility only 10% of patients with chronic-phase CML are currently eligible. Transplantation earlier in the chronic phase (within 1 year after diagnosis), the use of marrow from matched, unrelated donors and the development of improved methods for reducing the incidence of GVHD all hold promise. In addition, the preliminary results of intensive therapy followed by transplantation with cultured autologous marrow have been encouraging. If further progress is to be made, continued optimism coupled with carefully developed and executed studies will be necessary.