The Treaty of Rome (1957) declared a common European market as a European objective with the aim of increasing economic prosperity and contributing to "an ever closer union among the peoples of Europe".

implementing a common monetary policy, the euro was introduced as a legal currency and the 11 currencies of the participating Member States became subdivisions of the euro. Greece joined on 1 January 2001 and so 12 Member States introduced the new euro banknotes and coins at the beginning of this year.The successful development of the euro is central to the realisation of a Europe in which people, services, capital and goods can move freely.12 Member States of the European Union are participating in the common currency. They are: Belgium Germany Greece Spain France Ireland Italy Luxembourg The Netherlands Austria Portugal Finland  Denmark, Sweden and the United Kingdom are members of the European Union but are not currently participating in the single currency. Denmark is a member of the Exchange Rate Mechanism II (ERM II), which means that the Danish krone is linked to the euro, although the exchange rate is not fixed.The elected governments of Member States together created and developed the euro. In Madrid in December 1995, the European Council adopted the name “euro”.The European Central Bank (ECB) was established on 1 June 1998. It is based in Frankfurt am Main, Germany, and aims to maintain price stability and to conduct a single monetary policy across the euro area.This is done through its own activities and through working with the national central banks. Together, the ECB and the euro area national central banks are known as the Eurosystem.The NCBs of Member States not participating in the euro area, i.e. Denmark, Sweden and the United Kingdom, have a special status which allows them to conduct their own national monetary policies, but not to take part in deciding and implementing monetary policy for the euro area.The EurosystemThe national central banks of the euro area together with the ECB are known as the Eurosystem.The Eurosystem's primary objective is the maintenance of price stability. It meets its objectives through: deciding and implementing monetary policy; conducting foreign exchange operations; and operating payment systems. The NCBs of the participating Member States played a key role in the smooth transition to the euro. Their responsibilities have included: introducing the euro in their respective countries; managing the changeover from national currencies to the euro; creating the necessary systems to effectively circulate the euro banknotes and coins; withdrawing national currencies; and providing advice about and promoting the use of the euro.