Of 52 children aged 9 months to 16 years old with acute myelogenous leukaemia (AML) in first complete remission undergoing bone marrow transplantation at our institution, 31 received allogeneic transplants (allo-BMT) and 21 received autologous transplants (ABMT). Initial induction and consolidation chemotherapy were not uniform. BMT was performed at a median of 7 months (range: 2.5 to 22.5 months) from the diagnosis. Conditioning included chemotherapy (n=43: 4 x 4 mg/kg of busulfan and 3 x 60 to 70 mg/m(2) of melphalan) or total body irradiation (12 Gy) plus chemotherapy (n=9). Graft-versus-host disease (GVHD) prophylaxis in allo-BMT cases consisted of methotrexate +/- cyclosporin A. Unpurged marrow was used in ABMT cases. All patients showed sustained engraftment. Amongst allograft cases, acute or chronic GVHD developed in 7 patients each (23%). 8 patients (15%) died (5 with allo-BMT, 3 with ABMT), including transplant-related mortality in 3 of the allo-BMT patients. 7 patients had relapses (3 with allo-BMT, 4 with ABMT). As of June 1999, 43 patients are alive and well 13 to 160 months after BMT (median, 71), with 5-year disease-free survival rates after BMT of 84% for allo-BMT, 81% for ABMT and 83% altogether. Although the presented data are based on a retrospective evaluation, we consider BMT for childhood AML during first complete remission an effective treatment for eradicating leukaemia.