Usage-based theories hold that the sole resource for language users’ linguistic systems is language use (Barlow & Kemmer, 2000; Langacker, 1988; Tomasello, 1999, 2003). Researchers working in the usage-based paradigm, which is often equated with cognitive-functional linguistics (e.g., Ibbotson, 2013, Tomasello, 2003), seem to widely agree that the primary setting for language use is interaction, with spontaneous face-to-face interaction playing a primordial role (e.g., Bybee, 2010; Clark, 1996; Geeraerts & Cuyckens, 2007; Langacker, 2008; Oakley & Hougaard, 2008; Zlatev, 2014). It should, then, follow that usage-based models of language are not only compatible with evidence from communication research but also that they are intrinsically grounded in authentic, multi-party language use in all its diversity and complexities. This should be a logical consequence, as a usage-based understanding of language processing and human sense-making cannot be separated from the study of interaction. However, the overwhelming majority of the literature in Cognitive Linguistics (CL) does not deal with the analysis of dialogic data or with issues of interactional conceptualization. It is our firm belief that this is at odds with the interactional foundation of the usage-based hypothesis. Furthermore, we are convinced that an ‘interactional turn’ is not only essential to the credibility and further development of Cognitive Linguistics as a theory of language and cognition as such. Rather, CL-inspired perspectives on interactional language use may provide insights that other, non-cognitive approaches to discourse and interaction are bound to overlook. To that aim, this special issue brings together four contributions that involve the analysis of interactional discourse phenomena by drawing on tools and methods from the broad field of Cognitive Linguistics.