Institutional discourse is the specialized discourse used by social actors in various institutional contexts, such as law courts, universities, and public administrations, among others. This type of discourse can, of course, vary widely: it can be written or oral, formal/informal, use various channels (e.g., e-mail,Web site), and exploit various registers and genres. In all these varieties, the discourse is very “managed” in the sense that lexical, grammatical, and rhetorical choices made by speakers and writers are crucial in implementing their goals. The interest in analyzing institutional discourse is evident when we consider the huge amount of scholarly and research work carried out over the past decades (e.g., Sarangi & Roberts, 1999; Thornborrow, 2002; Mayr, 2008). As Roberts (2011, p. 81) puts it: “the study of institutional discourses sheds light on how organizations work, how ‘lay’ people and experts interact and how knowledge and power get constructed and circulate within routines, systems and common-sense practices of work-related settings.” The focus of this entry is to describe the grammatical features of institutional language in both written and spoken mode. More specifically, institutional communication is here analyzed in relation to two contexts: academic and legal. The literature abounds with different definitions of institutional discourse. To our purpose, a brief outline of some seminal definitions is given here with the aim to provide an idea of what is generally assumed in the literature with respect to these concepts, without any attempt at completeness.