Prompted by the increased visibility of inclusive pedagogies, the present article discusses the concept of “inclusion” in relation to foreign language teaching from a linguistic perspective. The foreign language classroom constitutes a special environment that poses specific language-related challenges to inclusive education. In an effort to face these challenges, the present article elaborates how linguistic research and insights can contribute to an implementation of inclusive foreign language education. In terms of theorisation, the narrower and broader senses of educational inclusion are outlined, the notion of “linguistic barrier” is introduced, and various ways in which linguistic exclusion may manifest itself are identified. It is argued that purely cognitivist approaches to second language acquisition are insufficient for achieving higher levels of inclusivity, as they do not cater for the social and contextual aspects that shape practices of exclusion and inclusion. Alternative approaches such as sociocultural theory are shown to be better equipped for this purpose. Various prominent exclusion-related dimensions are discussed with respect to their repercussions in language and linguistic practices, among them exclusion related to learners with special needs, ethnicity, gender, sexuality and non-native language users. Suggestions are made of how to proceed methodologically in linguistic investigations of exclusionary practices, with the aim of creating effective, linguistically based inclusion strategies. It is suggested that typological, discourse analytic and ethnographic linguistic approaches are most promising in this respect. The concluding section recapitulates central aspects that have surfaced in the theoretical and methodological discussion, calls for inclusion-oriented changes in foreign language teaching and highlights conspicuous parallels between the inclusive EFL classroom and English as a lingua franca communication.