Data on 5572 children and adolescents diagnosed with malignant bone tumours (International Classification of Childhood Cancer, Group VIII) before the age of 20 years during 1978-1997 in Europe were extracted from the Automated Childhood Cancer Information System (ACCIS) database. Age-standardised incidence among children during the period 1988-1997 was similar for boys and girls aged 0-14 years (5.5-5.6 per million). Among adolescents aged 15-19 years, males had higher incidence (19.3 per million) than females (10.7 per million). Among children, osteosarcoma accounted for 51% of registrations and Ewing's sarcoma for 41%. Among adolescents, 55% of registrations were osteosarcoma and 28% Ewing's sarcoma. Both tumours had their highest incidence in late childhood or early adolescence. There were no significant time trends in incidence during 1978-1997. Five-year survival estimates for patients diagnosed during 1988-1997 were, respectively, 59% and 51% among children and adolescents with osteosarcoma and 62% and 30% among children and adolescents with Ewing's sarcoma. Between 1978-1982 and 1993-1997, survival increased for both children and adolescents with osteosarcoma, and for children with Ewing's sarcoma.