The European economic and financial crisis was caused by a mix of debt and banking problems. The crisis spread from the US to Europe through the banking system. The imbalance in the European Monetary Union countries' payments played a big role. The crisis showed that problems can quickly move between closely connected economies. The payment system of EMU countries became very important during the crisis. To solve the crisis in the long term, more political unity is needed, including a shared budget and banking system. In the short term, countries with extra money, like Germany, need to spend more to help everyone recover.