David Cameron has promised to offer voters an in/out referendum on EU membership should his party win next year's general election.
First, however, he has committed himself to renegotiating the terms of Britain’s membership in a bid to persuade eurosceptics to stay in the EU.
Here's exactly what he wants from Brussels...
1. An agreement that the “ever-closer union” laid down in EU treaties does not apply to the UK.
2. An end to ‘benefit tourism' from EU migrants who allegedly do not come to the UK to work but for its welfare state.
3. More power for national governments, less power in Brussels.
4. Powers allowing “groups” of states to reject unwanted EU legislation.
5. New controls on immigration from new members as they join the EU.
6. An end to “unnecessary interference” from the European Convention on Human Rights.
7. Fewer regulations and an end to “excessive interference” by the EU in how businesses are run.
8. Limits on the right of citizens of countries already in the EU to migrate to the UK to find work – the most-important of the so-called “red lines” and the one that could be hardest to achieve.
However, EU president Jose Manuel Barroso told the BBC's Andrew Marr Show yesterday that Cameron's plan to cap the number of EU workers holding jobs in the UK would break EU rules - and those rules are not likely to change just to suit the UK.