This chapter examines the design, implementation, and impact of a year-long EMI faculty professional development (PD) course developed by adapting the curriculum of a postgraduate Applied Linguistics (TESOL) programme at a university in Singapore. Designed and conducted as a funded capacity-building programme for STEM faculty members from five universities in Vietnam, the course purposefully placed equal emphasis on both the “E” and “I” in EMI, drawing on curriculum design processes and relevant principles of language instruction as its pedagogical foundation. In this chapter, I analyze the syllabus, pedagogical materials, faculty assignments, and module feedback from the course, highlighting possibilities and challenges of connecting TESOL and EMI for the design and implementation of EMI faculty PD courses. The chapter concludes with suggestions for faculty developers with backgrounds in TESOL, language teacher education, and classroom discourse who wish to design and implement similar PD courses for EMI faculty.