Citizenship is the status of persons recognized according to the custom or law of the country that gives that person - citizen, rights and duties of citizenship. Citizenship is acquired by origin, birth in the territory of a State, naturalization and by international treaties. In Croatia, citizenship, and the rights and obligations of a citizen, and the possibility of termination of citizenship, defined by the Law on Croatian citizenship. Every nationality has to be recorded in exactly the prescribed books, a certificate issued to a citizen called the certificate of citizenship and fulfills the special vrstomcrne ink. By joining the European Union, Croatian citizens have the right to citizenship of the European Union. When a person has both given citizenship, is said to have dual citizenship. In addition to the citizenship of the European Union, a person can have dual citizenship in the sense of citizenship of two different countries. Usually, this citizenship acquired by birth and citizenship acquired origin, or of the nationality of the parents.