Data from a national survey (n = 1666) of researchers, practitioners, and policymakers in the field of rural mental health services were used to conduct a sociometric analysis of person-to-person communication in the field. This article describes the structure of the person-to-person communication network in terms of its connectedness, centrality, homogeneity, and differentiation. Despite the diversity of survey respondents, and apparently meager interorganizational communication, communication in he field is similar, in many respects, to that observed in "invisible colleges." While the probability of two randomly chosen individuals being in contact is low (0.0008), over 70% were connected indirectly. The person-to-person communication network is also highly centralized and exhibits higher than expected communication among respondents in the same professional role, type of work organization, and geographical region. It does not appear to be highly differentiated with respect to topic, since the majority of information providers are contacted with respect to a number of topics.