The paper explores engagement as a linguistic category by discussing its defining characteristics. Following work by Evans and colleagues (2018a, b), we discuss issues of scope and the intersubjective distribution of information, as central to the definition of engagement. In addition, we examine the notion of access as a crucial component of engagement marking and we attempt to distinguish access from epistemic authority, which we argue is a prerequisite for the existence of engagement as a linguistic category. Both access and epistemic authority appear central to an analysis of engagement marking, as found in the literature and in the languages of this Special Issue. From an interactional point of view, engagement may be viewed as a form of “stance” (Du Bois 2007), in that it primarily positions the speech participants with respect to talked about events from the point of view of the speaker.