To determine the feasibility of obtaining bone marrow cells from cadaver donors for transplantation, marrow cells were prepared from 17 cadaver donors. After surgical removal of the iliac crest, as many as 2 X 10(9) cells were isolated. Cadaver marrow had a lower percentage of T cells (mean of 10%) than did marrow from living donors. The T cells were lysed by a monoclonal antibody and human complement to a point at which no sheep red blood cell-rosetting cells were detected. Low levels of T colonies, however, grew out from the monoclonal antibody-treated cells. Although cell loss inevitably occurs from purification, antibody treatment, freezing, and thawing, sufficient numbers can be recovered for transplantation. The yield of stem cells was 84% for CFU-C, 39% for CFU-E, 81% for BFU-E, and 48% for CFU-GEMM. We suggest that T cell- depleted marrow cells from cadaver donors could be used for transplantation. Improved immunosuppressive therapy may be required, however, to prevent graft rejection of allogeneic marrow that may have minor histocompatibility differences.