I have drawn insights from my work on the single market, EU trade policy, and EU participation in international regulatory cooperation, as well as the work of others to try to explain EU policy-making more broadly. In this I have been very lucky to co-edit with Helen Wallace (University of Sussex), Mark Pollack (Temple University), and Christilla Roederer-Rynning the sixth, seventh, and eighth editions of Policy-Making in the European Union (Oxford University Press, 2010, 2015, and 2020). My understanding is best reflected in Chapter 3 – “The European Policy Process in Comparative Perspective.” This chapter acknowledges that policy-making in the EU is particularly complex and is distinctive, but contends that it can, nonetheless, be fruitfully studied by drawing upon insights from the analysis of policy-making within states and cooperation among states. It argues that theories rooted in Comparative Politics and International Relations can explain different phases of the EU’s policy process. In doing so it helps to explain why policy-making varies across issue areas within the EU.