The main purpose of this master thesis is to investigate in what ways library and public preschool cooperate with families with immigrants background in developing and protecting children's languages and cultures in two districts, Hässleholmen and Norrby, in the community of Borås. I want to investigate the parent's meaning of view according to which roles the libraries and public preschools involvement play. The study is based on qualitative interviews. Nine interviews were undertaken with parents who live in these two districts and five interviews with the librarians and preschool teachers who work in the libraries or the public preschools. The study of relevant literature, which describes topics such as psychological aspects of immigration, facts about children with immigrant's background and their language development and multicultural librarianship, provides a basis for the discussion. The results show that cooperation between library and public preschool and their involvement is very important for those immigrants families in many ways such as to preserve their own languages and cultures but also to help both children and parents to learn a new language. All parents I have interviewed enjoy to visit the public preschool and want the cooperation between the library and the public preschool to continue and develop.