This chapter elaborates on ways of carrying out a comprehensive review based on searching the research literature systematically in the context of English Medium Instruction (EMI). Teaching content subjects in English is now a growing phenomenon around the world. Many researchers, teacher educators and teachers want to read and understand the latest findings of studies on EMI. A systematic review, which ‘systematically’ locates all relevant studies, evaluates these studies’ findings and synthesizes the findings that have implications for teaching and learning in EMI, can provide numerous benefits to researchers and writers. First, it draws readers’ attention to different findings about the same issues in the literature, such as the use of native languages (L1) in EMI classrooms, translanguaging pedagogy (i.e. refer to a pedagogical process of utilizing more than one language in a classroom) and learning in EMI. It can also indicate whether a consensus exists on effective ways of teaching and learning in EMI classrooms. A well-structured systematic review in which writers follow existing review protocols reduces the potential bias inherent in synthesizing research. For example, some of the standard procedures that are agreed on in the research community (e.g., PRISMA guidelines) include review teams having diversified research expertise, inter-rater reliability checking, rigorous screening procedures, data extraction, and assessment of the quality of studies. These procedures can largely eliminate bias and offer the EMI research community authoritative information about gaps in the research that need to be filled. By examining the evidence in the research, they can highlight conflicting views on the same teaching issues in the context of EMI. In this chapter, we use a case study that explores the teaching and learning issues encountered by teachers and students in EMI science classrooms, introducing different approaches to carrying out research reviews, particularly reviews that use quantitative approaches, such as systematic quantitative reviews and meta-analyses. We outline the key steps when conducting a systematic review: (1) formulating the topic; (2) locating and screening the literature; (3) evaluating the data; (4) extracting the data and assessing the study quality; (5) analyzing the data; (6) interpreting the results; (7) presenting the results; and (8) writing up the review. The implications and limitations of writing a systematic review in the EMI context are discussed.