Seven countries are waiting in the wings to join the European Union.
Croatia and Turkey started accession talks on 3 October 2005. Turkey could complete them in 15 years, Croatia in five.
The other Balkan countries have been told they can join the EU one day, if they meet the criteria. These include democracy, the rule of law, a market economy and adherence to the EU's goals of political and economic union.
Click on the map to learn more about them