Abstract
Electronic networks of practice (ENOP) exist primarily through computer-mediated exchange and are social spaces where individuals working on similar problems selforganize to help each other and share perspectives about their occupational practice or common interests. This exchange of knowledge through message postings produces an online public good, where all participants in the network can access the knowledge, regardless of their contribution. Thus, this research builds upon theories of collective action and public goods to better understand the provision and maintenance of knowledge in an electronic network of practice. We use social network analysis to examine the following research questions: I) what is the pattern of contribution that produces and sustains the ENOP public good, 2) are ENOPs characterized by a critical mass constituting a core? and 3) how does the heterogeneity of resources and interests of participants impact ENOP collective action? We find that the network of practice is sustained through generalized exchange, is supported by a critical mass of active members, and is shaped as a star. The critical mass is significantly related to occupational tenure, expertise, availability of local resources and a desire to enhance one's reputation.