In a keynote speech at a conference on Iceland’s currency options, European Central Bank Vice-President Boris Vujčić said the euro area’s expansion to 21 members shows that the Maastricht convergence criteria and participation in the Exchange Rate Mechanism II have provided a durable framework for joining the single currency. He presented ERM II as more than a waiting period, describing it as a mechanism for policy coordination, institutional preparation and confidence-building that tests whether convergence is credible and sustainable. Vujčić recapped the four economic convergence criteria for euro adoption, covering price stability, sound public finances, long-term interest rates and exchange rate stability, with ERM II participation required for at least two years. He said the framework has been flexible enough to accommodate varied country experiences, citing the Baltic states, Slovakia, Croatia and Bulgaria, and argued that post-crisis reforms including the Single Supervisory Mechanism, the Single Resolution Mechanism, stronger macroeconomic surveillance and reinforced fiscal governance have complemented the original framework. Close cooperation within the banking union ahead of euro adoption has consequently become an important element of the ERM II entry process.