This chapter demonstrates how the speculative attacks on sovereign bonds in 2010s were designed and executed, and how they consequently worsened the Eurozone crisis. It also examines why a sovereign bond crisis was avoided during the pandemic. These attacks were possible because of the particular composition of the Economic and Monetary Union (EMU) as well as the institutional design of the European Central Bank (ECB). Goldman Sachs designed financial derivatives for the Greek government in order to enable it to hide the real size of the Greek public debt. The deal also enabled the investment bank to anticipate, and profit from, the sovereign debt crisis. The rise of spreads on sovereign bonds triggered austerity, while there is a direct correlation between the intensity of the austerity measures and the intensity of attacks on sovereign bonds. The mutualization of debt via Eurobonds is described in 2010 as being an unmanageable and illegal concept; in the 2020s, however, it was a solution for the crisis together with the ECB interventions.