This ethnographic study investigates how a project group deals with the contradiction between distributed knowledge in boundary-spanning collaborative processes and the expectation that software systems will provide unified, codified knowledge. Group and individual activities were observed over a period of 18 months, to examine the ways knowledge was presented, recognized, shared, or otherwise managed during joint design of business process and IT systems change. The study explores how knowledge and expertise were translated across organizational boundaries, and identifies four stages in the development of group understanding of how to manage sensemaking and expertise across knowledge boundaries: focus on defining shared goals; acknowledging and sharing tacit knowledge about organizational practice; identifying external influences; and explicit knowledge generation.