Data on more than 50,000 registrations in the Automated Childhood Cancer Information System (ACCIS) database were used to present an overview of regional patterns in childhood cancer incidence in Europe during 1988-1997, and to present additional detail on selected carcinomas whose occurrence in childhood is seldom described because of their rarity. Total age-standardised incidence was 138.5 per million for Europe overall, and varied between regions from 131.1 per million in the British Isles to 160.1 per million in Northern Europe. Incidence varied significantly between regions for nearly all diagnostic groups. The greatest range of regional incidence rates was for central nervous system (CNS) tumours, from 27.0 per million in the West to 43.8 per million in the North. Differences in registration practice for non-malignant tumours account for some of this variation. There was a marked excess of carcinoma in Eastern Europe, which was wholly attributable to the high incidence of thyroid carcinoma in Belarus, though there was also evidence of inter-regional variation attributable to differences in registration practice. The geographical heterogeneity of incidence rates for other diagnostic groups seems more likely to reflect variations in underlying risk.