More than 95% of children with acute lymphoblastic leukemia (ALL) achieve complete remission with conventional chemotherapy and 60 to 70% are cured. In contrast, only 70 to 80% of children with acute myeloid leukemia (AML) achieve remission and 30 to 40% are cured. In acute leukemia, ALL and AML, high initial white blood cell counts, poor initial response to therapy, certain structural chromosomal abnormalities, and diagnosis under 1 year of age indicate an increased risk of relapse. Prognosis is poor in children, who relapse during treatment. If no bone marrow donor is available, high dose chemo(radio)therapy and autologous stem cell rescue can be applied in these children to consolidate second remission. Furthermore, autologous bone marrow transplantation may be used to consolidate first remission of individual children, who suffer from acute leukemia with high risk criteria. 19 children with a median age of 8 years (0.5 to 19 years) underwent high dose chemo(radio)therapy and autologous bone marrow and/or blood derived stem cell rescue. 11 suffered from ALL, 4 had AML, and 4 suffered from Non Hodgkin's lymphoma (NHL). 7/13 children (54%), who were in first or second remission after early relapse, are alive in continued remission for median 24 months (9 to 44) after autografting. Children in more advanced stage of disease had no benefit from high dose therapy and autologous stem cell rescue.