This award funds the author's well known work on time, interaction and performance in groups and on the flow of work in technologically enhanced groups. The researcher conducts a set of experiments that deal with the consequences for group interaction and task performance, of variations in communication channels and modalities within work groups. The research compares face to face groups with groups doing comparable tasks in which communication is computer-mediated. The theory guiding this work contains the assumption that various forms of technological enhancement in such groups simultaneously reduce some barriers to effective group performance and impose others, and that they do so by altering the informational, temporal, and interactional processes by which the group does its work. The empirical basis underlying this theoretical rationale, however, consists of findings from only a very thin base of research studies, some of which have serious methodological flaws. This research conducts a series of experiments that are robust and replicable.