School segregation, understood as the unequal distribution of various social groups in the schools of a territory, is of extraordinary importance for the equity and equal educational opportunities of the population. A good part of the studies on school segregation approximate the phenomenon by calculating indices that provide a general image of the educational system in different territorial contexts, allowing comparisons between them, but they do not report on the political or social conditions of territorial and educational contexts that can clarify the conditioning factors of the segregation processes. This article analyses the school segregation of students of foreign origin in the schools of the city of Valencia (Spain). The analysis relates the segregation indices of the system as a whole, of the city districts and of the ownership of the centres with data from residential segregation in the same territory, with the distribution and characteristics of the centres, and with an approach to family strategies. The results suggest multiple processes of segregation in which the schools reflect the residential segregation of their surroundings and emerge, in addition, segregations of a strictly school nature conditioned by the educational policy, the selection of schools and the strategic choice of families.