The Australian higher education context has seen an increasing number of international students and academics, including those from a non-native English speaking (NNES) background. Whilst the issue of the English language as a means of communication for NNES international students has been well researched, the communicative and pedagogical challenges facing educators, especially those from NNES backgrounds, in teaching and supervising students in English have been overlooked. This paper aims to explore the challenges in teaching using English as a medium of instruction (EMI) and associated strategies of academics from NNES backgrounds. Adopting a Vygotsky’s socio-cultural theoretical perspective, the study conceptualises EMI as a mediational tool academics appropriate in mediating their teaching delivery. This study adopted a mixed-method approach, using semi-structured individual interviews and survey questionnaire with academics from a range of disciplines, including STEM (Science, Technology, Engineering & Mathematics) and HASS (Humanities, Arts, and Social Sciences) disciplines, at an Australian university. Findings revealed multiple communicative and pedagogical challenges facing academics in providing effective delivery in English. The study also reveals strategies successful academics applied to adapt the tool – the English language- to effectively mediate their teaching delivery for student learning. The findings have implications for professional development programs and institutional support for NNES academics teaching in contexts with English as a native language. The findings could also contribute to supporting academics develop effective delivery in EMI and facilitate curriculum transformation in the ever changing context of higher education.

Keywords: English-medium of instruction, academic professional development, learning and teaching in higher education