Social discrimination, defined as the relative preference for intra-ethnic over inter-ethnic relationships, was studied in pupils' networks in Dutch secondary school classes. While native Dutch pupils (ethnic majority members) mainly named fellow majority members, ethnic minority members reported ties with as many majority as minority members. Considering the ethnic composition of the classroom, however. majority members discriminated less than minorities. No strong effect of classroom ethnic composition on social discrimination was found, whereas neighborhood composition was shown to clearly influence social discrimination: ethnic minority members were more, and majority members less inclined to discriminate in neighborhoods with more ethnic presence. (C) 2009 Elsevier B.V. All rights reserved.