This book offers essential insights into the challenges and complexities surrounding the medium of instruction (MOI), its impact on all languages and stakeholders in multilingual contexts, educational processes, developments and outcomes.

MOI has been a prominent topic in recent debates on the role of languages in education in multilingual contexts, partly because prioritizing one language over others as the medium of instruction has a profound impact on all languages and stakeholders in multilingual contexts. These include, to name but a few, (language) teachers, teacher educators, students, and policymakers, as well as industries and enterprises built around the needs and expectations of these stakeholders.

This book presents high-quality empirical research on education in multilingual societies. It highlights research findings that, in addition to providing descriptions of language learning, development and use in language contact and multilingual contexts, will help shape future language education policy and practices in multilingual societies.

Indika Liyanage (Ph.D.) is an Associate Professor in TESOL and Discipline Leader for TESOL/LOTE at Deakin University, Australia. He is also an Honorary Professor at the Faculty of Education, Sichuan Normal University, and Researcher at the Centre for Multi-culture, Sichuan, China. Indika has been a language teacher educator and doctoral supervisor for many years. He has published extensively and worked as an international consultant on TESOL in the Pacific.

Tony Walker (Ph.D.) is a Research Fellow in TESOL and LOTE at the School of Education, Deakin University, Australia. He worked in Australia as an English teacher and language teacher educator for many years, and continues to publish in the field, and to work with teacher educators in Asia as an international consultant on academic writing.

Chapter 1. Medium of instruction and Multilingual contexts: Unravelling the questions and unpacking the challenges (Indika Liyanage).- Chapter 2. Language alternation as an interactional practice in the foreign language classroom (Anna Filipi).- Chapter 3. Multilingualism and language mixing among Singapore university students (Kingsley Bolton).- Chapter 4. Educational globalization and the creation of split identities (Francois Victor Tochon).- Chapter 5. Bilingual Education classrooms in Sri Lankan schools: A social space for ethnolinguistic reconciliation (Harsha Wijesekera).- Chapter 6. CLIL for who? Commodification of English-medium courses in Japan's higher education (Kayoko Hashimoto).- Chapter 7. Benefits of translanguaging and transculturation exchanges between international higher degree research students and English medium research supervisors (Minglin Li).- Chapter 8. Trilingualism and Medium of Instruction Models in Minority Schools in Qinghai Province, China (Ma, Fu).- Chapter 9. Children's views and strategies for making friends in linguistically diverse English medium instruction settings (Maryanne Theobald).- Chapter 10. English in a Mongolian Ethnic Minority Primary School (Yi Yayuan).- Chapter 11. Scrutinising Critical Thinking (CT) in Chinese Higher Education: Perceptions of Chinese Academics (Anhui Wang).- Chapter 12. Media of instruction in Indonesia: Implications for bi/multilingual education (Tony Walker).