This study was designed to identify factors that best predicted the amount and perceived benefits of network use. A 70-item electronic mail survey measured five categories of variables: personal attributes, environmental characteristics, perceived media characteristics, usage, and outcomes. It was returned by 66% of a random sample of 300 network users. Respondents were active network users with high levels of teaching tenure, schooling, and computer experience, and convenient access to equipment needed to use the Internet. Outcomes reported for network use mainly centered around professional development activities, whereas personal and instructional outcomes were less frequently reported. Multiple regression equations predicted 28% of amount of use, 46% of variety of uses, 45% of professional benefits, 16% of personal gratifications, and 25% of instructional outcomes. Socially oriented factors appeared repeatedly in these equations. Social integration with a community of users entered all but one of the equations, social presence contributed to the prediction of each type of outcome, and number of contacts regularly reached via the network was associated with both amount and variety of use. These findings suggested that network facilitators should implement strategies to increase interactions among potential and current network users and to enhance perceptions of the systems' social presence.