This chapter outlines the internal imperfections of the European Economic and Monetary Union (EMU), which led to the Eurozone crisis and are relevant with regard to fragility manifested in the 2020s. These are related to the macroeconomic vulnerabilities of smaller economies and their dependence on the euro. When the global financial crisis struck the Eurozone, all these imperfections were unmasked and intensified. This chapter explains the centre–periphery division within the monetary union and discusses the evolution of different viewpoints concerning the Greek crisis. At the beginning of the Eurozone crisis, theoretical approaches were mostly focused on endogenous social, economic and political causes. However, with the geographical and temporal extension of the turmoil in the Eurozone, analyses which interrogated the EMU instead of just Greece began to gain attention. Different strategies for governance of the crises in the 2010s and the 2020s are also discussed.