Abstract
This chapter examines the impact of constitutional interpretation on the relationships between national and subnational governments within a framework that emphasizes the role of judges. It begins by defining federalism and detailing how (judicial) constitutional interpretation has gained prominence in federal systems. The analysis identifies which court cases qualify as ‘federalism jurisprudence’, arguing against a narrow focus solely on power allocation and advocating for the inclusion of cases related to self-rule and shared rule as well as fundamental rights. This broader understanding facilitates an exploration of the (de)centralizing effects of constitutional interpretation.The discussion addresses whether courts serve as centralizers or decentralizers, identifying four key methodological challenges in answering this question. Finally, the chapter analyzes why constitutional interpretation tends toward either centralization or decentralization, concluding with insights into its implications for federal governance.