The debt crisis has affected five euro area countries. It has been particularly intensive in Greece. The paper examines potential implications of declaration of the government insolvency (“sovereign default”). It does not necessarily have to result in a country’s exit from a monetary union and replacement of the euro with new national currency. Such process is subject to an assessment of costs and benefits in the trade, capital outflows, and impact on the banking sector. The paper also concludes that a withdrawal from a monetary union does not always have to lead to adverse effects on the position of the euro within international relations. This is determined by the structure of creditors (official vs. private creditors), reaction of investors (subject to economic importance of the affected country), and measures taken by the monetary union’s central bank. These conclusions are also relevant decisions (in economic policy) relating to the euro adopting in the Czech Republic.