Of 33 patients who had undergone allogeneic bone marrow transplantation during first complete remission of acute nonlymphocytic leukemia, 21 patients have now been followed in continued complete remission for 6-64 mo (median greater than 18 mo) without maintenance chemotherapy. The median age of the surviving patients is 27 yr. Transplant-related complications occurring throughout the first year after marrow grafting were fatal in 7 patients, and leukemic recurrence led to the death of 5 patients. The actuarial long-term disease-free survival is 60% and the actuarial remission rate is 79%.