This chapter examines EU financial regulation1 before and after the financial crisis and in advance of the anticipated break up with the United Kingdom. It provides background and analysis to help readers grasp the current state of affairs and to think clearly about likely future ones. There is no shortage of pressing questions. Will future Brussels policies in this sector contribute to financial markets characterized by a desirable balance of industry risk-taking, systemic stability, and protections for consumers and investors? Will the EU’s policies continue to constitute a piece of the international financial architecture or reflect a home-grown approach as in other regulatory areas like data privacy and chemicals? Will Brussels and Washington remain the principal global rulemakers, together setting transnational standards, or can we expect a different configuration of regulatory power, perhaps with London either allied with Washington or becoming the swing player? As these questions suggest, EU financial regulation cannot easily be examined in isolation. More so than the other policy areas covered in this volume, the region’s regulation of finance is deeply intertwined with transnational institutions and international politics.2