Croatians are voting in a nationwide referendum on whether to join the debt-stricken European Union.
The vote is a test of how much the 27-nation bloc has lost its lustre with its troubled economies and bickering leaders.
A pre-vote survey suggests that between 56% and 60% of those who take part will answer "yes" to the question: "Do you support the membership of the Republic of Croatia in the European Union?"
Those who support the EU say the Balkan country's troubled economy could only profit from entering the bloc's wider markets. Opponents say Croatia has nothing to gain by entering and will only lose its sovereignty and national identity.