This thesis is based on the question of how ideas expressed in the documents that control public libraries are embodied in the physical library, thus making it possible for said ideas to make a real social difference. The purpose of the study is to investigate if and how library space design promotes certain patron behaviour and how this relates to multilingualism. The thesis takes as its point of departure French philosopher Michel de Certeau’s way of looking at how sites are managed and used: a producer creates place through an overall strategy and a consumer creates space by using the site tactically. Methodologically, the study was conducted using analysis of library usage through ideal type cases constructed based on participant observations at a Swedish public library. The results of the study and the analysis of said results are organized thematically, focusing mainly on library space and patron behaviour. Some of the conclusions that can be drawn from the study are that the library as place expresses the intellectual content of laws and guiding documents and that the patrons/consumers using the library in a manner consistent with the producer’s strategy benefit from its design and that those who do not are hence disfavoured. Another conclusion is that patron multilingualism should be considered when analysing library usage from this point of view.