European Union: How nations become EU members
Albania is waiting in the wings, while Macedonia is further ahead in the queue. But Iceland sounds like it is not really bothered any more.
Opinions in the UK are divided on whether Britain should stay in. But some in Zagreb were excited when Croatia became the latest member to join the European Union this summer.
Adam Fleming reports from Brussels for Politics Europe on the hurdles to climb for those wanting to join, when he spoke to EU Croatian Ambassador Mato Skrabalo and EU Albanian Ambassador Mimoza Halim.
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