Croatia’s EU accession process began by the end of the 90’s. In 1997 the Council of the EU laid down the political and economic preconditions for developing bilateral relations with Croatia and in 1999, at the proposal of the European Commission, the Stabilization and Association Process for the countries of Southeast Europe, Croatia included, was adopted. In 2000 high level representatives of the EU and the countries included in the Stabilization and Association Process gathered for the Zagreb Summit, where the negotiations for the Stabilization and Association Agreement (SAA) were opened.
By signing the SAA in Luxembourg on 29 October 2001, Croatia entered contractual relations with the Union for the first time. The country became a potential candidate and started comprehensive preparations for the membership of the European Union. Upon its ratification in the Croatian Parliament, the European Parliament and in all EU Member-States’ national parliaments, the SAA entered into force on 1 February 2005.
Croatia applied for EU membership on 21 February 2003 and, after getting the European Commission’s positive opinion in April 2004, it was granted the status of candidate country in June 2004. This opened the way for starting accession negotiations, officially launched on 3 October 2005, when the first Intergovernmental Conference between the EU Member States and Croatia was held. The basis of negotiations were Croatia and the EU’s negotiating positions, individually elaborated for each chapter based on the results of analytical overviews.
Croatia closed the negotiations on 30 June 2011. Their results now make an integral part of the Treaty of Accession, signed by Croatia on 9 December 2011 in Brussels. The provisions of the Treaty stipulate that it will enter into force on 1 July 2013 subject to it being ratified by Croatia and all the EU Member States in conformity with their constitutional provisions.
On 23 December 2011, the Croatian Parliament adopted the decision on calling a state referendum on the accession of the Republic of Croatia to the European Union. It was decided that the referendum would be held on 22 January 2012.
Before that, on 19 January 2012, the Croatian Parliament adopted the Declaration on the Membership of the Republic of Croatia of the European Union as a Strategic Interest of the Republic of Croatia, by which it called all the citizens of Croatia to come out to cast their vote in the referendum, express their democratic will and thus contribute to the development of Croatia as a state of democratic, pluralistic and open society.
At the referendum held on 22 January 2012 the citizens of Croatia supported Croatia’s membership of the European Union with 66.27% "for" votes. When the Accession Treaty entered into force on 1 July 2013, Croatia became the 28th Member State of the European Union.