Thirty-eight children between the ages of 0.8 and 17 yr with acute nonlymphoblastic leukemia in 1st remission induced by chemotherapy were given cyclophosphamide, total body irradiation, and bone marrow transplants from HLA-matched donors. Six patients died of pneumonia, 1 died of metabolic problems, and 1 died of chronic graft- vs. host disease complications. Five patients relapsed between 6 mo. and 3.2 yr after transplantation. Three of the 5 died of leukemia, 1 survives with leukemia 3 yr after transplantation, and 1 survives in remission off treatment following chemotherapy for 22 mo. Twenty-five survive in continuous remission from 1.7-8.4 yr after transplantation, and the actuarial analysis shows a disease-free survival rate of 64%, with a plateau extending from 3.5-8.4 yr. All lead normal lives.