EU newcomers from eastern Europe are generally much more positive about the bloc than their older counterparts.
Here is a look at opinion polls in some of the 10 eastern European states that joined the European Union in 2004 and 2007, ahead of Croatia's entry on July 1.
The biggest country in central Europe remains a keen supporter of the European project nine years after joining the bloc.
Some 73 percent of Poles were in favour of the EU, according to a poll by the CBOS institute in April, with 19 percent against it. In 2007, enthusiasm was at its height with 89 percent supporting the EU.
With political leaders who are notoriously critical of Brussels, Czechs are much more eurosceptic than their neighbours with just 30-40 percent of the population saying they trust the EU, according to various polls.
The figure has dropped constantly since 2010 when it still topped 50 percent.
A 2004 newcomer, Slovakia is one of the bloc's most euro-optimistic members.
According to a Eurobarometer survey from February 2013, a total 71 percent of Slovaks said they felt like EU citizens, while 72 percent believed free movement within the EU would benefit their economy.
Hungarians have grown more tired of the EU along the years, helped by Prime Minister Viktor Orban's aggressive anti-EU rhetoric and frequent attacks on Brussels.
In a referendum in April 2003, 83.76 percent of the population had voted to join the European Union. The number has since dropped but was still 66 percent in March 2013, according to the Median polling institute.
One of the last countries to enter the EU in 2007 and still its second poorest member, Romania is nevertheless a euro-enthusiast country.
A total 74 percent of Romanians said membership was positive in a survey by the Ires polling institute in May. This was up four points from last summer, while 65 percent of people said Romania benefitted from the EU.
Once a model EU member, Slovenia is now struggling in a recession that has hurt EU enthusiasm.
In a referendum in 2004, 89.64 percent of voters backed EU accession. If the vote was to be held today however, only 44 percent of citizens would vote in favour, while 43 percent would oppose joining the EU, a poll by Ljubljana University's Center for Public Opinion Research found last week.