The move towards the internationalisation of higher education institutions has sparked the creation of different approaches to learning through additional languages. Owing to its global recognition as the lingua franca of academia, English is the predominant additional language in most circumstances. Under the guise of national and supranational regulations, English-medium instruction (EMI) is gaining ground rapidly. However, before rushing to offer EMI programmes, there are issues that must first be resolved and others that should be appropriately monitored during implementation since they involve crucial decisions connected to the language of instruction that may seriously affect the quality of the programme. One such issue is whether or not these programmes should be part of wider language policy in higher education, and if decisions are based on clear definitions regarding language use. In this chapter we review the role of the language in EMI, examine the need to provide scientific evidence of the programme outcomes, and identify potential areas of further research such as the attention to language in academic contexts.