French municipal libraries, faithful in their entirety to the republican "model" of integration, do not generally offer resources in the spoken languages of immigrants. However, some have built up collections in these languages and continue to enrich them. Ought not these isolated initiatives to become general practice, so allowing readers of foreign origin to maintain links with their own culture, and also contributing to the promotion of these cultures amongst all the other readers? For librarians, it constitutes a difficult job, requiring suitable methods. It is possible to formulate some proposals inspired by French and foreign experiences, in particular Scandinavian and German.