Presented is a case study of several scientific communities which used a computerized conferencing system (Electronic Information Exchange System--EIES) for a period of two years to enhance their communications and carry out cooperative tasks. Though it focuses on one particular system, it was designed to yield some data that make possible direct comparisons with the results of studies of other computer-mediated communication systems. Specific areas examined are: (1) the determinants of acceptance of this new form of communication; (2) user reactions and preferences related to specific system features and design choices and how these change with experience; and (3) changes in communication patterns, work patterns, and productivity-related measures as a result of using the system. (Author)