Introduction

The definition of English medium instruction (EMI) varies (Gundermann, 2014; Macaro, 2018). One prominent definition refers to EMI as “the use of the English language to teach academic subjects (other than English itself) in countries or jurisdictions where the first language of the majority of the population is not English” (Macaro, 2018, p. 19). However, other researchers have critiqued this definition for being too narrow and limiting the scope of EMI to contexts where most of the population has English as a second language (L2). Pecorari and Malmström (2018) suggest a wider definition of EMI that encompasses Anglophone countries. Although populations in such countries are predominantly English first language speakers, classrooms often include English as a second language (ESL) students (and teachers). Countries such as Australia and New Zealand, for example, have high numbers of international students from a range of first language backgrounds and a high proportion of domestic students from migrant backgrounds, although teachers and lecturers may not necessarily be aware of their students’ linguistic backgrounds (Baker & Hüttner, 2017, 2019). Following Pecorari and Malmström (2018), this book adopts a wide definition of EMI and uses the term to refer to the instruction of disciplinary classes delivered in English regardless of whether most, many, or only some students in the class are using English as a second or foreign language.