One for all and all for one? Case studies of prototypes in commercial projects

The HCI discipline has long promoted the communication and collaboration between usability experts and intended users of systems. We present case studies that highlight the importance of representations in communication between not just usability experts and end users, but also graphic designers, clients, and technologists. Our case studies are used to illustrate the need to select appropriate representations for the target audience and the stage of system development. We argue that relationships can be identified between representation fidelity, target audience, and stage of development. These relationships can then be used to inform the appropriate selection of representations.