Changes in treatment of ANLL in children over 23 years (1968-90) and advances made in the last ten years in a pediatric hematological unit are reported herein. Of 124 patients under 15 years of age, 18 of whom were infants, 118 were evaluable. Of these, 58 were treated before 1980 and, although complete remission (CR) was attained in 75%, the median duration was lower than 12 months and no patient survived in CR more than 6 years. From 1981 to 1987, 40 patients received one or two induction treatments followed by three consolidations and then blocks of sequential intensive chemotherapy for 12-15 months. CR was attained in 87.5% and event-free survival (EFS) was 22.5% at 8 years: 14% for those treated from 1981 to 1983 and 33% for those included in the ANLL-84 protocol. In 1988, a post-remission protocol with intensification therapy (two high-dose ARA-C treatments combined with mitoxantrone in the first and amsacrine in the second) followed by allogeneic or autologous bone marrow transplant (BMT) was initiated. Of 20 patients included, 17 reached CR (85%) and 16 underwent BMT. EFS of the 20 patients was 65% at 2 years and post-BMT relapse-free survival was 75%. These results are compared with those obtained separately with present intensive chemotherapy protocols and with BMT and it is concluded that intensification treatment followed by BMT (allogeneic or autologous) might constitute an advance in the treatment of children with ANLL.