Goodwin M., Jones M. and Jones R. (2005) Devolution, constitutional change and economic development: explaining and understanding the new institutional geographies of the British state, Regional Studies 39 , 421-436. This paper is concerned with the new institutional geographies of devolution and state restructuring, particularly in the UK. As part of perhaps the biggest change to the UK state since the Acts of Union, the Labour Party has established the Scottish Parliament, elected Assemblies for Wales, Northern Ireland, and London, and Regional Development Agencies within England's regions. The paper offers a conceptual framework through which to explore these new institutional geographies. It extends Jessop's strategic-relational approach to the state by arguing that it is no longer enough simply to refer to a multivariate 'hollowing out' of the nation state in an era of economic and political restructuring. The paper suggests that devolution represents a geographically uneven 'filling-in' of the state's institutional and scalar matrix, which is leading to an increasingly complex spatial division of the state. This appears to be creating uneven capacities to act and the implications of this are discussed.