We describe the participation patterns in scholarly mailing lists and analyze its implications for the design and implementation of collaborative distributed multimedia. A mixed-methods design included both a qualitative study and an E-mail administered survey. The qualitative study objective was to determine the forum's patterns of use from the user's point of view. The E-mail survey objective was to determine participants' patterns of use. Interaction in these electronic forums was far from a many-to-many interactive exchange. The central dimension emerging from the qualitative study was the fragility of users' binding to the forums (transient membership, preference for a broadcasting recipient role, and weak involvement in the message exchange). These findings were corroborated by the E-mail survey results. The results suggest that participation in the construction of a communal information space is not without problems. Some of the difficulties detected in the participation in electronic forums could be amplified when participation involves the composition of multimedia messages. These increased contributing costs can further unbalance the incentive structure for contributing to the shared communal information space. Strategies to change the incentive structure involve decreasing contribution costs by facilitating technology learning and use, and increasing incentives to contribute messages. Given these considerations, it appears that collaborative distributed multimedia should follow a model more like tailored collaborative distributed multimedia systems for specific communities of professionals dealing with very special problem areas, where the use of collaborative distributed multimedia is the best way to advance the knowledge base of the group.