This chapter explores the territorial nature of European politics. It suggests that policy making in Europe resembles a system of multilevel governance in which policy authority at the national level is increasingly shared with European Union (EU) institutions at the supranational level, and regional governments at the subnational level. In order to understand the complex relationships between these different levels government, this chapter familiarizes students with the key concepts to understand multilevel politics, such as the pooling and delegation of policy authority as well as federalism and decentralization.