|Recent research in our group has focused on tabletop interface design, with an emphasis on identifying design guidelines that facilitate group work. We have developed several collaborative tabletop applications, and have evaluated them through formal usability studies and informal walkthroughs. However, while we have had success in evaluating the usability of specific aspects of the tabletop interfaces (aspects of what Pinelle et al.  refer to as “taskwork”), the impact of the interface on the “teamwork” dynamics is far more difficult to judge. We hope that this workshop will provide a stepping-stone for developing a standard for quantitatively and qualititatively describing the impact of groupware technology on collaboration.