A group of people that work together in the same spatial environment relies on various possibilities to observe the activities of partners, to monitor the progress of a project or to recognise the development of group structures. Such activities are often recognised peripherally; nevertheless, they stimulate spontaneous and informal communication. Although the computer supported co-operative work (CSCW) research area yielded a number of systems and solutions that enable and support distributed co-operation processes, distributed work is still significantly more difficult to manage than co-located work. A significant reason for this is the missing perception of the activities and actions within a distributed group. Therefore, distributed groups often suffer from a lack of awareness of the common activities. Co-operation partners are often not aware of activities of other co-operation partners that are relevant for their own work. The synchronisation problems resulting from this often lead to decision problems, misunderstandings or duplicated work. Thus, effectiveness, spontaneity, and social orientation possibilities in distributed teams are limited. The social forces which facilitate the behaviourmilieu synomorphy in an environment – that is, in a behaviour setting (Barker, 1968) – are very limited in electronic spaces. Awareness support can make the difference between an electronic behaviour setting and a pure electronic space (Pankoke-Babatz, 2000). Apart from the lack of awareness of actions that could be co-operative, there are limited opportunities for chance meetings. In the local working environment, coincidental meetings often initiate communication and the exchange of experience and knowledge. Prussak (1997) describes this phenomenon very appropriately: “If the water cooler was 011