Digital documents are a frequent part of everyday work in business and government of which we know little. Using Wegner's community of practice (COP)[26] lens, two cases of ad hoc digital document interactions in organizations are presented and analyzed. Digital documents are found to play roles as objects of practice, reifications of practice, and boundary objects; indeed, one document may take on all of these roles. Documents-digital or otherwise- are important for accomplishing, coordinating, and learning in today's complex, knowledge-based work. COPs prove useful for studying these technologically dependent phenomena, while their dependence on an opaque infrastructure becomes most visible when the infrastructure fails. Providing document-supportive in-formation technology is complicated by the need to respond to a technology of practice experiencing an independent trajectory of development. Further, linkages between COPs such as boundary practices highlight the complex organizational work (digital) documents are called on to perform.