The banking union is an EU-level banking supervision and resolution system which operates on the basis of EU-wide rules. It is comprised of 3 main building blocks: (1) The single rulebook, (2) The single supervisory mechanism, (3) The single resolution mechanism. It aims to ensure that the banking sector in the euro area and the wider EU is safe and reliable and that non-viable banks are resolved without recourse to taxpayers' money and with minimal impact on the real economy.