The arrival over the last 15 years of a substantial number of pupils of immigrant origin has presented Catalan schools with significant challenges. The schools in Vic (70 km north of Barcelona) have been at the forefront of attempts to adjust to this new multicultural reality. This article describes the results of three studies carried out by the Educational Research Group of the University of Vic (GREUV) at critical points in this process. The studies focused on the effects of local decisions taken to balance the social composition of schools, the attempts by some schools to adopt an integrated approach that involves other agencies in order to improve pupils' learning opportunities, and the effectiveness of different strategies for the reception of newly arrived pupils and their families. The article concludes with some elements of analysis and reflection that might contribute to improving the educational opportunities offered by schools with newly diverse pupil populations. (Contains 16 notes, 2 tables and 1 figure.)