Dual citizenship is the simultaneous possession of two citizenships. It arises because there is no common international law relating to citizenship. The most common reasons for dual citizenship are these:

• Marriage to a citizen of another country;
• Birth in a country that grants citizenship by birth, to parents who are citizens of a country that grants citizenship by descent.
• Adoption by parents who are citizens of another country;

Not all nations recognize that their citizens may possess simultaneous citizenship of another country. For more information on dual citizenship, please visit the US State Department Services Dual Nationality website.