The purpose of this study was to determine the links between school adjustment, friendship, and identification with both the cultures of origin and with the host culture. Our overriding hypothesis was that integration in Berry’s terms, that is, simultaneous identification with both the culture of origin and the majority Spanish/Catalan culture, would predict better school adjustment. We also expected the same integrated acculturative stance to be linked with closer and less conflictual friendships. The participants were 682 students, in six public high schools in Catalonia, Spain. Of these, 226 were first- and second-generation immigrants, and this subset was used in most of the analyses reported herein. The results showed that acculturation to the host culture and acculturation to the culture of origin are both adaptive but in different ways. These results applied to both first- and second-generation immigrants. Identification with the culture of origin was a significant predictor of closeness in friendship. In contrast, identification with the host culture is linked with school adjustment. Integrated adolescents, who identify simultaneously with host culture and culture of origin, do best at school according to teachers but not significantly better than assimilated students, who identify primarily with the host culture.