We report on our experience of bone marrow transplantation (BMT) in children with acute myeloblastic leukaemia (AML) and high risk of relapse (initial WBC greater than 20 x 10(9)/l, FAB M 5, M 6, M 7). 32 children were grafted between november 1982 and october 1991 at the Children's Hospital of the University of Jena. Two patients underwent an allogenous BMT in relapse and died from progressive disease. In 13 children an allogeneic BMT was performed in first complete remission. One patient relapsed, two patients died from severe acute graft-versus-host disease, and two patients died from encephalopathy and cardiomyopathy. Eight of the 13 patients are living and well 18 months to eight and a half year after BMT. Seventeen patients received an autologous (unpurged) BMT. Four of them relapsed four to seven months after BMT. The disease free survival (DFS) for the 29 patients grafted in remission was 0.65. There was no statistical significant difference in DFS between patients with allogeneic and autologous BMT. We conclude that in children with AML and high risk for relapse BMT offers a real chance for better survival. Autologous BMT avoids the problems of graft-versus-host disease and of finding suitable donors for allogeneic marrow transplantation.