The global financial crisis of 2008 highlighted many shortcomings of banking supervision in the EU, in particular, the general limitation of banking supervision to the national level, and the failure to effectively oversee trans-national banking activities. Banks could take advantage of supervision arbitrage in European financial market. Thus, establishing a banking union is one of the most important reforms undertaken by the EU to address this supervisory failure. A banking union represents the Europeanization of banking supervision in the Euro-zone area, and marks a further acceleration of European Economic and Monetary Union and a new stage of European financial integration.This book applies legal interpretation, policy analysis and comparative study approaches, to provide a systemic, innovation and in-depth study of the three pillars of the banking union — the Single Supervisory Mechanism (SSM), Single Resolution Mechanism (SRM), and European Deposit Insurance Scheme (EDIS) — as well as the regulation of shadow banking and the future of a banking union in the aftermath of Brexit and COVID-19. This book examines the following key issues concerning the banking union: its background, legal framework, scope and contents, institutional mechanism, decision-making procedures, supervisory measures, practical operations, supplementary measures, and international cooperation, among others. Further discussions explore the meaning and implications of the banking union, and a comparison with the mechanisms with relevant laws and policies of Taiwan. Finally, proposals are offered for future banking supervisory reforms in Taiwan. This book should be an important reference for both academics and practitioners, and contribute to Taiwan’s financial stability.