PurposeThe purpose of this paper is to examine knowledge development across network boundaries.Design/methodology/approachThe empirical part of this paper is based on a longitudinal case study of a Swedish regional strategic network (RSN) in a sparely populated area. Data was collected through interviews, websites and social media. The case focuses on the creation of sub-networks designed to improve collaboration among different experts. The paper analyses how knowledge evolved across these sub-networks, the RSN and social and business networks.FindingsThe case study demonstrates how RSN membership can foster knowledge development by building social networks not only among CEOs but also among other key positions within firms. These sub-networks facilitate relationship-building, which may lead to business exchanges. However, their primary value lies in the exchange of experiences, mutual support and knowledge sharing, all of which contribute to various aspects of firm development.Originality/valueThe study offers a longitudinal perspective on how RSNs in sparsely populated areas can support knowledge development by enhancing social networking among participating firms. It highlights the creation of sub-networks that strengthen connections across various firm positions.