Starting with Houtkoop and Mazeland’s study of discourse units, and touching upon recent studies aimed at detailing unit projection in interaction, this article argues that the drive toward abstract and discrete models for units and unit projection is potentially misleading. While it has been established that to engage in talk-in-interaction, as it unfolds in real time, participants rely on projectable units, research aimed at defining units unintentionally backgrounds the contingency inherent in interaction. A central function of language for collaborative action (...) is the management of simultaneously unfolding facets of action, sound production, gesture, and grammar – produced by multiple participants. This article draws upon classic and current data analyses foregrounding linguistic/interactional practices designed to manage local contingencies. It is argued that attention to participants’ regular methods for managing and exploiting contingencies be incorporated from the outset in our descriptions of language and the nature of unit building in interaction. (shrink)