Jus soli (; ), meaning 'right of the soil', is the right of anyone born in the territory of a state to nationality or citizenship. As an unconditional basis for citizenship, it is the predominant rule in the Americas, but is rare elsewhere. Since the Twenty-seventh Amendment of the Constitution of Ireland was enacted in 2004, no European country grants citizenship based on unconditional jus soli. A study in 2010 found that only 30 of the world's 194 countries grant citizenship at birth to the children of undocumented foreign residents, although definitive information was not available from 19 countries.