Perceived Impact of EMI on Students’ Language Proficiency in Vietnamese Tertiary EFL Contexts

English as a Medium of Instruction (EMI) has been widely adopted at the tertiary level in non-English speaking countries and Vietnam is no exception. Vietnamese universities and the Vietnamese government have anticipated significant linguistic benefits for student outcomes through the implementation of EMI. Using a mixed-methods design of surveys, interviews, and focus groups with students and lecturers at six Vietnamese universities, this study investigates lecturer and student perceptions of the impacts of EMI on students’ language proficiency in Vietnam. The study indicates that both students and lecturers were optimistic about students’ language improvement. This study recommends some implications for students, lecturers, and further research regarding EMI in the Vietnamese EFL context. Among the recommendations to emerge from this study, assessment on students’ language ability before they commence EMI courses and lecturers’ adequate language competence for EMI programs should be considered.