Allogeneic transplantation remains an integral part of the management of hematologic malignancies. However, transplant-related mortality, graft-versus-host disease, and disease recurrence continue to be major limitations to successful transplant outcomes and challenges to investigators in the field. Newer approaches have focused on reduction of the intensity of the conditioning regimens, harnessing the antitumor effects of the allograft, and development of adoptive immunotherapy strategies to circumvent the limitations. These developments provide physicians with the ability to tailor transplants to specific patients and their diseases.