Participatory design amalgamates the expertise of interdisciplinary specialists with the taskspecific expertise of end-users. Groupware design is widely recognised as benefiting from participative approaches. Recognition of this ideal, however, does not preclude the failure of groupware design due to poor communication and inadequate understanding between participants. We provide a grounding in the problems affecting groupware success, and introduce four design principles that guide all those involved in design around the pitfalls that have been encountered, some repeatedly, by groupware.