We examine the unfolding dynamics of devolution and economic governance in the United Kingdom. We maintain that devolution has set in train a series of far-reaching organisational and institutional changes in the various UK territories. Although devolution in the United Kingdom can be described, following Jessop, as an aspect of the ‘hollowing out’ of the state, we argue conversely that the various UK territories are being ‘filled in’ in a number of important ways. The notion of ‘filling in’, we argue, draws attention to the spatially contingent impact of devolution on the various UK territories. We examine this process of ‘filling in’ specifically in the context of the economic governance of Wales. In particular, we focus on the creation of Education and Learning Wales (ELWa)—the body charged with improving the education and skills of the Welsh workforce, as well as with encouraging entrepreneurship within Wales. It highlights the need to consider: in an organisational context, the territorial and scalar structure of ELWa and its role in collaborating with other organisations of economic governance; and in an institutional context, the development of a new working culture within the organisation. Given the close associations between devolution and economic governance, we suggest that the success or otherwise of ELWa in overcoming these challenges has the potential to affect the future trajectories, and public and political evaluations, of devolution in Wales.