Sweden is continuously ranked high among the countries offering English-medium instruction. The country also ranks high in terms of its general proficiency in English but the use of this language in higher education and research has not been uncontroversial. On the level of language policy, “parallel language use” has been proposed in order to ensure the use of Swedish in all academic domains and in order to prevent English from “taking over”. However, this concept seems to be more politically driven than practically oriented, effectively promoting two parallel monolingual systems. In practice, there is a complex coexistence of different languages in a given educational context. Students and lecturers in EMI programmes use English as a lingua franca, which results in a diversity of Englishes, language-mixing, and different understandings of language norms. This chapter reviews previous research conducted on various aspects of EMI in Sweden, starting from language policy and its implementation, and then focusing more specifically on educational practices and students’ learning in EMI contexts, including academic writing in English. It concludes by placing the research reviewed in this chapter in the framework for the study of EMI proposed by Dafouz and Smit (2016) and identifying venues for further studies.