Historically Human Computer Interaction has drawn on cognitive models of human information processing. The focus of this approach is the individual “user” at the interface. However, in recent years the growth of interactive digital media and social networking sites has led researchers to turn to a view of “the user” as part of a social and cultural context, and to draw on theories that address social and cultural aspects of human action and interaction. In this talk, I will illustrate how we drew on both cognitive and social interaction theories when designing the installation of a number of interactive community displays in public places. While the underlying technology remained the same for each installation, social and cultural aspects of settings inspired the provision of different interactive interface elements. Through description of this work, I will illustrate how socially oriented experience- and activity-based theories of interaction drove the design and evaluation of the technology, and illuminated our understanding of interactive media sharing in physical and digital public places. I will end with discussion of how these grounding theories and principles are being drawn on as part of the emerging area of Media Experience Research.