Accession negotiations, which typically take years, are split into 35 chapters covering areas such as the economy, energy, rule of law and human rights, to help the applying country align its practices with European Union standards.
Montenegro began accession talks with Brussels in 2012. It now has 30 chapters open, including two new ones: freedom of movement for workers and services.
The EU also opened two for Serbia, on company law and external relations, bringing to 12 the total number of chapters open for the country, which has been in EU membership talks since 2014.