The regional scale continues to be considered critical to UK economic governance. Successive iterations have however seen limited impact in addressing enduring issues of uneven development despite significant reform. This paper argues for a reconceptualization of the region and regional geographies through application of an assemblage reading. Building on existing work in economic geography, it argues regional economic governance should be considered as an assemblage process involving overlaying territorialisations of place, policy, and stakeholders, and related dynamic capacities involving the multiplicity of components and interactions, legacies of prior arrangements, and agency of actors. Regional governance therefore occurs through a process of continual becoming. Similarly important here however is decoupling. Decoupling has significant spatial and sectoral implications as changed arrangements shift the dynamics integrating actors and groups of actors locally and regionally. Using analysis from Southern Staffordshire, part of the Greater Birmingham city-region, the article argues the shifting nature of regional assemblages and distinct forms of territorialisation are material in decoupling key local sectors from local economy and place. We conclude the application of an assemblage reading, and its enhancement through application of decoupling, has scope to illustrate key causes of uneven development within regions.