Today, discourse is studied in most disciplines of the social sciences and humanities. Yet one wonders what are the outlines of the field where this object is being studied. This contribution identifies two tendencies at work among the researchers of this field: on the one hand, disciplinary specialisation, which can be seen in the development of discourse analysis as a sub-field within linguistics, and, on the other hand, transdisciplinary articulations which have given birth to the transdisciplinary field of Discourse Studies. Discourse analysis has been well established in France and the United Kingdom since the 1970s while Discourse Studies is a phenomenon whose boundaries are still rather fuzzy. However, discourse analysis would never have been possible without the transdisciplinary debate in structuralism around power, subjectivity and language, which has made “discourse” a key notion in the social sciences and humanities. Since discourse is embedded in social life, it cannot be reduced to an object which can be accounted for by one discipline only. In order to inscribe these epistemological and intellectual challenges into the broader field of Discourse Studies, this contribution discusses the notion of discourse in the disciplinary spaces of the study of language, the social sciences and in the humanities.