This study reviews 105 articles concerning English-as-a-medium-of-instruction (EMI) taken from the Web of Science database (2005-2021). The growth trajectory, the productivity, co-citation analysis, and bibliographic coupling were performed to present the procedural change, the 'hotspot' themes, influential publications, authors, countries, sources, and knowledge domains. The trajectory development of EMI increased steadily from 2018 onwards. The most influential authors are identified as Piller, Cho, Kuteeva, Mattoo, Neagu, and Özden. The most influential journals are "Journal of Multilingual and Multicultural Development, Comparative Education, International Journal of Bilingual Education and Bilingualism, Current Issues in Language Planning, Higher Education, System," and "RELC Journal." Effectively, the most influential countries are Australia, the People's Republic of China, Sweden, the UK, the USA, the UAE, Spain, Singapore, Denmark, Japan, and South Africa. The research fronts cover numerous key topics on EMI policy for achieving internationalisation, practices of EMI programmes, trans-languaging/bi-lingual/multi-lingual education in EMI, the effectiveness of EMI in higher education, and the challenges of EMI implementation, such as 'nativeness' and national identity. Hotspot themes emerge and the potential trends are trans-languaging, teacher development, and trans-national higher education. The results may serve as a framework for educators, administrators, and policymakers to pursue EMI practices.