Between January 1979 and December 1980 64 children with acute lymphoblastic leukemia were treated in 9 pediatric clinics in austria according to the BFM study 76/790-protocol. For remission induction all patients received an 8 week multidrug regimen (West-Berlin ALL-protocol). High risk patients were defined according to a risk score at diagnosis and additionally treated with a 6 week reinforced reinduction protocol during the first half year after diagnosis. Maintenance therapy was stopped after about 22 months. The life table-analysis after 30 months showed a 75.5% disease free survival for the total group of patients. Compared with a control group of 228 patients treated between 1974 and 1980 in 9 different clinics in Austria according to 3 consecutive national treatment regimens (modifications of Memphis protocol VII and VIII), therapeutic results were markedly improved. After a follow-up of 36 to 90 months the overall oumulative remission rate was 37.7%. The results could be improved especially in the group of high risk patients for replase by 35% in contrast to the historical studies. A prognostic difference between low- and high risk-patients was not seen in the BFM study (84.3% vs. 69.9%). Without doubt, the marked improvement of prognosis is due to the intensification of therapy.