The paper provides evidence on the extent of ethnic segregation experienced by children across secondary schools and neighbourhoods (wards). Using 2001 Schools Census and Population Census data, indices of dissimilarity and isolation are employed to compare patterns of segregation across nine ethnic groups, and across Local Education Authorities in England. Looking at both schools and neighbourhoods, high levels of segregation are found for the different groups, along with considerable variation across England. Consistently higher segregation is found for south Asian pupils than for Black pupils. For most ethnic groups, children are more segregated at school than in their neighbourhood. The relative degree of segregation is analysed and it is shown that high population density is associated with high relative school segregation.