The development of a European single currency goes back to the 1950s.
The euro is the result of years of debate
1957: The Treaty of Rome said a common European market could increase economic prosperity and help towards promoting closer ties among the people of Europe
1969: European summit at the Hague makes a single currency an official objective
1970: The Werner report envisages the creation of a single currency over 10 years
1970s: The oil crises, economic divergence and a weak dollar meant only a "currency snake", tying the currencies of Germany, Denmark and the Benelux countries together, was achieved
1979: The European Monetary System (EMS) is created, with the exchange rate mechanism (ERM) defining rates in relation to the European Currency Unit (ECU), a quasi-currency representing an average of participating currencies.
1986: Single European Act The Single European Act, which modifies the Treaty of Rome is signed and comes into force the following year. It sets up a framework for the Single European Market by increasing the Commission's powers and introducing qualified majority voting for a number of issues.
1988: The European Council of Hanover sets up a committee chaired by Jacques Delors, the then President of the European Commission, to put forward plans leading to European Monetary Union
1989: After consideration of the Delors report, the European Council meeting in Madrid agrees the first of three stages of EMU will begin in July 1990
1990: Stage one of EMU begins with narrowing of bands under the Exchange Rate Mechanism and closer co-operation on economic policy and between banks.
1991: Plans for a single currency by the year 2000 are agreed under the Treaty of European Union Plans by the 15 members of the European Union in the Dutch town of Maastricht.
Strict rules for those joining are agreed, including targets for inflation, interest rates and budget deficits
The UK and Denmark exercise their opt outs from the stage three of EMU.
1994: Stage two of EMU begins with plans for creation of European Central Bank and convergence of member states' economic and monetary policies.
1995: The name "euro" is chosen for the new currency at the European Council in Madrid.
1997: New UK Chancellor Gordon Brown announces five economic tests to be assessed before the UK joins the euro.
1998: The European Council agrees that 11 member states - Belgium, Germany, Spain, France, Italy, Ireland, Luxembourg, the Netherlands, Austria, Portugal and Finland - are ready to adopt the euro on 1 January 1999
European Central Bank established in Frankfurt to maintain price stability and set interest rates in the eurozone.
1999: Stage three of EMU: The euro is launched as an electronic currency used by banks, foreign exchange dealers, big firms and stock markets. Exchange rates of the participating currencies are set and eurozone countries begin implementing a common monetary policy.
2000: A referendum in Denmark ends with 53% of Danish voters rejecting entry to the euro.
2001: Greece joins the euro
The UK's Labour government, re-elected for a second term, says it will assess its five tests for euro entry within two years.
2002: Euro coins and notes become legal tender and national currencies become obsolete.
Sweden announces plans to hold a referendum on euro entry on 14 September 2003.
2003: The UK Government says it has decided the time is not right to recommend euro entry in a referendum.
Chancellor Gordon Brown says he will return to the issue again early in 2004.