This article analyses the changing trends in regional economic development policy delivery in multilevel governance systems. Although the imperatives of coordination of public policy interventions across multiple levels has generally been recognized, not enough attention has been given to how different political systems actually adapt their institutional and policy designs to effectively operate in the emergent complexity of multilevel governance systems. The article focuses on regional economic development policy governance in the province of Ontario, Canada over the past three decades, drawing insights from new regionalism, organization theory and governance literature to examine the prospects and challenges of policy delivery in politically complex multilevel systems. The case study illustrates how regional economic development policy is increasingly dictated by complex environmental and institutional forces of multilevel governance that are shaped by the particular character of a political system.