This chapter presents a study of the linguistic milieu that is generated when students from different parts of the world meet and interact in international university settings. The study is conducted in nominally English-medium courses at a Swedish university, and focuses on how students use Swedish and other non-authorised languages in addition to English. The multilingual characteristics of the milieu are exemplified and discussed, and it is demonstrated that the language of the surrounding society holds a special position. In the era of globalisation, universities are part of internationalisation processes, but yet situated in a local context marked by a certain history and specific linguistic resources.