As ubiquitous computing technologies mature, they must move out of laboratory settings and into the everyday world. In the process, they will increasingly be used by heterogeneous groups, made up of individuals with different attitudes and social roles. We have been studying an example of this in a campus setting. Our field work highlights the complex relationships between technology use and institutional arrangements – the roles, relationships, and responsibilities that characterize social settings. In heterogeneous groups, concerns such as location, infrastructure, access, and mobility can take on quite different forms, with very different implications for technology design and use.