The biggest group in the European Parliament, yet one from which British MEPs are absent. This used to be the home of the British Conservatives before they left to find allies in a new Eurosceptic group.
Along with the Socialist group, the EPP has always been one of the two powerhouses of the Parliament, providing most of the Presidents, Vice-Presidents and Committee chairs.
It is broadly centre-right and enthusiastic about deeper EU integration.
As its name suggests, this is the group where British Liberal Democrats can be found. It is the main centrist group in the Parliament, although in reality it spans the spectrum from social liberals to economic liberals.
Traditionally, though, it is the most fervently pro-integration of all the political groups.
Former Belgian Prime Minister Guy Verhofstadt is the group's leader.
As its name suggests, this group is an alliance of two parties - the European greens, and the European Free Alliance, which primarily represents parties focused on regional interests such as the SNP, Plaid, and regional parties from Flanders, Catalonia and Corsica.
The Swedish Pirate Party have also signed up to this group, which generally takes a left of centre position on most issues. Naturally this is the home of the UK's two Green Party MEPs.
It is co-chaired by Daniel Cohn-Bendit from France and Rebecca Harms from Germany.
The origin of this group can be found in David Cameron's desire for the Conservatives to leave the federalist European People's Party and set up a new right of centre and Eurosceptic group.
After a trawl, the Conservatives found a sufficient number of potential allies - MEPs from seven different member states - to form a new group.
Aside from the Conservatives - and the associated Ulster Unionist Party - most of the other members in the group are from major parties in Poland and the Czech Republic, as well as a number of smaller parties.
British Conservative MEP Martin Callanan is the group's leader.
This is the group that can be found on the far left of the political spectrum, containing as it does members from a number of Communist and traditional Socialist parties.
Sinn Fein provides the sole UK representative in this group. Broadly Eurosceptic, the group takes a strong position on areas such as workers' rights and employment law.
It is chaired by a former member of the East German Communist party, Gabriele Zimmer.
Non-Inscrits (NI) - 27 MEPs
And so to those MEPs who have not been able to find enough friends or allies to form a group of their own, or who have been rejected by other groups.
Some non-attached members come from far right groups such as the BNP or France's National Front.
However it also contains MEPs who feel they do not fit into any of the other groups, such as the Democratic Unionst Party's sole MEP. Being unattached means that members have much less access to speaking time in the chamber, as well as fewer administrative and secretarial resources.
Numbers correct as of 21 January 2012. Source: European Parliament
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.