This chapter explores the concept of genre in three major traditions: Rhetorical Genre Studies (RGS), which views genres as typified social actions; Systemic Functional Linguistics (SFL), which defines them as staged, goal-oriented social processes; and English for Specific Purposes (ESP), which focuses on genres’ communicative purposes, schematic structures, and moves (e.g., Swales’ CARS model). It discusses how ESP has selectively integrated insights from the others to meet specific learner needs, often targeting a mix of academic and occupational genres. Accordingly, we distinguish between professional genres and pedagogical classroom genres, including occluded and mutt genres. The chapter also notes the proliferation of emerging digital genres (e.g., video scripts, data reports) that demand additional interdisciplinary skills of novice learners in ESP courses.