Single Display Groupware (SDG) lets multiple people, each with their own input device, interact simultaneously on a single display. With two or more people potentially working in the same or nearby areas of the display, the actions of one could interfere with others, e.g., by raising menus and bringing tool palettes into areas where others are working. Interaction techniques could be used to mitigate the interference; however, other approaches might be more suitable if collaborators were to

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... rally partition their workspace into distinct areas when working on a particular task. To determine the realistic potential for interference, we investigated people performing a set of collaborative drawing exercises in a co-located setting, paying particular attention to the locations of their interactions in the shared workspace. We saw that spatial division occurred consistently and naturally accross all participants, rarely requiring any verbal negotiation. Particular divisions of the space varied, influenced by seating position and image semantics. These results have several implications for the design of SDG workspaces, including the consideration of peoples' seating positions at the display, the use of moveable Local Tools and in-context menus, and the use of dynamic transparency to mitigate interference.