This chapter investigates the subject of e-collaboration and proposes a meta-taxonomy that classifies the existing taxonomies of collaborative systems found in the literature. It also points out the three dimensions in e-collaboration: communication, cooperation, and coordination. The most commonly encountered functions of collaborative systems are identified through an extensive review of commercial and research products. The functions and the systems are classified with relevance to the communication, cooperation, and coordination dimensions. We find that although all three dimensions of collaboration are necessary for the successful completion of work, there is a lack of an integrated system enabling all of them. Consequently we present the C-CUBED system, which attempts to support all three collaboration dimensions.