How Policy-Specific Factors Influence Horizontal Cooperation among Subnational Governments: Evidence from the Swiss Water Sector

Horizontal cooperation among political systems is crucial for addressing large-scale and boundary-crossing policy problems. This article introduces and analyzes policy-specific factors that help to explain horizontal cooperation among subnational-governments. It thereby builds on but specifies arguments from the literature on horizontal federalism that has usually been focusing on general institutional and societal factors to explain cooperation. These factors capture how a given policy problem unfolds (problem pressure), the ways in which subnational governments are exposed to and experience its consequences in similar or unequal ways (functional interdependencies and their symmetry), and how the issues are treated domestically (problem awareness). We illustrate the potential importance of these factors by analyzing treaties among Swiss substates in the water domain and relying on network analytic methods. We find that problem awareness and functional interdependencies and their (a)symmetries are important, whereas problem pressure has a mixed influence, depending on the issue area.