Epstein-Barr virus (EBV)-associated lymphomas following bone marrow or solid organ transplantation are often sensitive to immunomodulatory therapies. These have included withdrawal or reduction in immunosuppressive therapy in the solid organ transplant setting and adoptive cellular therapies in the bone marrow transplant (BMT) setting. We describe a strategy for generating EBV-specific cytotoxic T cell therapy lines with substantial killing activity against haploidentical targets. Weekly stimulation of peripheral blood mononuclear cells (PBMCs) for 3 weeks with the irradiated cells of an autologous EBV-transformed B lymphoblastoid cell line (B-LCL), followed by stimulation in the presence of IL-2, yielded T cell lines that were cytolytic for haploidentical B-LCLs but did not lyse haploidentical targets not expressing EBV antigens.