Lord Owen insists he is pro-Europe but not pro-euro

This is the newest of all the campaign groups fighting Europe's Economic and Monetary Union (EMU). Launched by the former SDP leader Lord Owen, it has the support of Lord Healey, the former Chancellor of the Exchequer, and Lord Prior, a member of Margaret Thatcher's first cabinet. Martin Taylor, the former Chief Executive of Barclays, and City economist Roger Bottle are other prominent members.

The group says that it is in favour of the European Union, but opposed to the single currency.

This group, financed by multi-millionaire businessman Paul Sykes, was formed from the remnants of Sir James Goldsmith's Referendum Party, which unsuccessfully launched candidates across the country at the last general election.

Several leading businessmen have clubbed together to put the case that monetary union would harm British business. A spokesman for the organisation says that they are talking to anti-euro politicians across the political spectrum, but try to distance themselves from "this is a German plot to win the war by other means" groups at the nationalist fringe.

The group says it is speaking for British business, but this is disputed by industry associations in favour of EMU. Critics claim that many members of Business for Sterling would lose out if monetary union would introduce sharper price competition in e.g. the retail sector.

Other business associations critical of EMU are the Institute of Directors and the Federation of Small Businesses.

This think-tank was founded last year by Tory peer Lord Pearson of Rannoch, who is said to believe in the UK's complete withdrawal from Europe.

Bill Cash, the man whose anti-EU stance caused so much political trouble for Prime Minister John Major, is the man behind the European Foundation. He is critical of all things coming from Brussels.

Baroness Thatcher is the icon of UK euro-sceptics

When Margaret Thatcher delivered a stridently anti-Brussels speech in 1988, eurosceptics from across Britain flocked to her banner and founded the Bruges Group to support her. Baroness Thatcher is now the group's honorary president.

One of the many homes for EU and EMU-sceptic Tory Lords and MPs. Lord Pearson of Rannoch is once again the driving force and among its many vice-presidents are former chancellor Norman Lamont and a long list of MPs, among them Iain Duncan-Smith, Nigel Evans, Michael Fabricant, Teresa Gorman, David Heathcot-Amory and Sir Michael Spicer.

This group actually does not exist yet. It is designed to serve as an umbrella group for all anti-EMU activists. The plan is said to have the backing of Conservative party leader William Hague and will be chaired by Sir Michael Spicer.

Labour's Denzel Davies believes monetary union could harm the UK

A group of Labour activists deeply suspicious of economic and monetary union - and thus a minority in New Labour. It is dominated by politicians like Lord Shore of Stepney and Denzil Davies.

This is the place for left-wingers to put their case against the euro, but tied to members of the Labour party.

The leadership of most UK trade unions is in favour of monetary union, but those who are against the single currency have joined the campaign against euro-federalism.

A group that says it is has members from all major political parties in the UK and claims that it has 220 branches across the country.

All party organisation that was set up during the referendum on whether the country should join the common market. It is run by Lord Stoddart of Swindon and Sir Richard Body, a Tory backbencher.

There are numerous other anti-EMU groups in the UK, among them the Albion Movement, the New Alliance, the Critical European Group, the Oxford Campaign against a Federal Europe, the Campaign Against the Single Currency, the UK Independence Party and many more.

The case in favour

While it may be difficult to keep track of the euro's enemies, the proponents of monetary union have only a few organisations to turn to.

Ex-Labour leader Neil Kinnock wants Britain to join EMU - befitting for a European commissioner

The European Movement will be the main force in the pro-euro campaign in the UK. Labour MP Giles Radice is president, ex-Chancellor Ken Clarke, EU commissioner Neil Kinnock and Lord Jenkins of Hillhead are vice presidents.

It is a cross-party group that fought for UK membership in the common market and now has taken up the cause of monetary union.

The European Movement has 8,000 members across the country.

This organisation will launch shortly and is supposed to act as an umbrella group for all pro-EMU groups in the UK. Its leader is Lord Hollick, linking it closely to New Labour, but euro-fans from all parties are expected to participate. The financial backing will come from some of the UK's top companies who are in favour of monetary union.

Lord Hollick has asked the PR agency Shandwick to co-ordinate the pro-Euro campaign.

A group of businesspeople in the City strongly in favour of EMU.

The Centre is a think-tank set up to boost the pro-European argument in the UK. The organisation enjoys the support of politicians from across the political spectrum.

Kenneth Clarke, a Tory but in favour of monetary union

There are a few pro-Europeans left in the Tory party, and Conservative mainstream is the umbrella group uniting them. Its board is chaired by Michael Heseltine.

This group of One-nation Tories says it has more than 1,000 members, is strongly in favour of free-markets and wants the UK to sign up to the single currency. Part of Conservative Mainstream.

Its members are pro-European Conservative MPs. Part of Conservative Mainstream.

This are the grass-roots euro fans among the Tories, and the group is formally registered as part of the Conservative party. Part of Conservative Mainstream.

Tory business leaders who are in favour of monetary union support the Action Centre, and the group is headed by Michael Welsh. Part of Conservative Mainstream.

Not formally part of Conservative Mainstream, but it is expected to play a key role in co-ordinating pro-European action at Westminster.

This is the place for Labour MPs to talk Europe, and argue the cause for Britain joining monetary union.