Enlargement EU enlargement: which countries are next to join
Several countries are in various stages of EU accession talks. Here's the current state of play — which candidates are closest and what hurdles remain.
Enlargement 
Debate The case for and against EU enlargement
Expanding the EU to new members would transform the bloc. Here are the strongest arguments on both sides of the enlargement debate.
Europe The Western Balkans’ long road to EU membership
Several Western Balkan countries have been EU candidates for years — some for decades. Here's why accession has stalled and what would need to change.