Ethnographic workplace studies in design tend to focus on the existing work practices either to inform the initial design of new information technology (IT) systems or as studies evaluating work practices after a system has been implemented and taken into use. However, ethnography may also prove efficient in identifying, analyzing, and evaluating changes in work practices that emerge from using the IT system as part of the design and implementation of this system. This is possible since the technical frameworks used for large IT systems are becoming highly configurable. This article presents an example from a case where a fully functional prototype of a large Electronic Patient Record (EPR) system was designed, implemented, used as a pilot study, and subjected to evaluations based on ethno- graphic observations. The case demonstrates how a new and important role for ethnography can be established as an integral part of iterative approaches to design and organizational implementation of large IT systems. The role of ethnography can be expanded from a descriptive role (describing ex- isting work practices or the situation after a complete implementation) to a constructive role focusing on appropriating new IT to the work practices of the users.