The implementation of English Medium Instruction (EMI) often involves the top-down imposition of policies, frequently overlooking the potential educational benefits for instructors, especially those whose teaching effectiveness may be compromised when delivering courses in English as a second (ESL) or foreign language (EFL). This research addresses this oversight by examining the EMI course process in terms of subject content delivery, instructional methods, and linguistic adaptability. Thirty Turkish native-speaking EMI lecturers were selected through purposive sampling and interviewed. The qualitative data obtained were subjected to content analysis. The findings reveal that instructors do not consistently adhere to specific teaching methodologies and largely rely on instructional tools such as PowerPoint presentations and brief video materials. During the EMI course process, several challenges became evident, including learner-related and lecturer-related problems. Notably, both learners and lecturers exhibited low levels of language proficiency, and there were significant measurement and assessment challenges. These findings underscore the need for improvements in language proficiency and pedagogical practices related to instruction and assessment. Stakeholders in higher education are urged to take necessary actions to address these issues, enhancing the overall effectiveness of EMI courses.