This Element introduces the theory of segmented polity to address the misfit between dominant state-centric political theories and the hybrid realities of contemporary governance. Segmented polities are contested, partial, and constrained but nonetheless develop autonomous policymaking capacities and distinct social constituencies. The EU exemplifies this form, blending supranational and intergovernmental traits within a statist political order. Grounded in organization theory and institutionalism, the Element provides empirical analysis of the internal market and security segments showing how segmented polities operate across functional domains and generate bounded epistemic communities. While enabling policy efficiency, they also exhibit democratic deficits. The Element presents segmented polities as evolutionary responses to governance complexity and outlines implications for political science, international relations, European integration theory, and democracy studies, and proposes a research agenda focused on longitudinal, actor-based, and comparative studies of polity segmentation beyond the EU. This title is also available as Open Access on Cambridge Core.
