Fragmentation is a ubiquitous characteristic of today’s global environmental governance architectures. Still we lack a robust framework to measure degree of fragmentation that can generate comparative data across different issue areas. To address this gap, this study applies a network perspective to map and measure the degree of fragmentation of actor-constellations in the architecture of global climate governance. First, a framework is developed to measure degree of fragmentation based on network measures. Second, a mapping of organizations and institutions is made. Third, two networks are created: a Virtual Policy Network (VPN) with organizations as nodes and hyperlinks as edges; and a Membership Network (MN) based on mutual memberships of organizations and institutions. Results show above 1000 organizations active globally in a network with low density and low modularity. The article presents a novel way of measuring fragmentation of governance architectures which enables researchers to compare fragmentation across issue-areas.
