Space is often designed based on the representations of user activities (i.e. lists, organograms or flowcharts) that streamline user activities in stepwise, oversimplified, representations that may leave insufficient room for future activity development. However, design can anticipate activity development if users are able to represent their own activities while participating in the design process. A case study of a medical imaging centre reveals that once users have such opportunity, their spatial practices are not only taken into account but also expanded. The designers, the users and the researchers created a range of instruments to expand across three units of analysis: operations, actions and activities. As a result, the representations of space proffered by the designers were expanded to a space of representation for the users, where new ways of working were realized. Based on this study, an integrated model for the production of space and the development of activity is proposed.