This chapter explores a relatively neglected aspect of these socio-political dynamics of the work performed by boundary objects; that is, the communicative practices embodied within objects themselves when deployed across boundaries created by professional specialisms. We argue that previous research on the role of objects in knowledge integration privileges the social interaction and communicative practices that occur around objects, over the communication that objects themselves embody; objects themselves are often ‘blackboxed’. Yet, many objects used by professionals in knowledge integration efforts, such as design drawings in architectural work (the focus of our study), embody text and talk (e.g., comment, description and annotation) as well as visual representation (e.g., drawing). This chapter explores the socio-political dynamics embodied within objects and how these define the possibilities for coordinated action and knowledge integration in architectural work. In so doing, we address an important lacuna in boundary object literature, which is that it' specifies communicative practices and the associated relations among participating communities. It does not, however, offer a compelling conceptualization of how the materiality of the medium interacts with recurrent and typified communication practices'(Osterlund, 2008:6).