Contains data on dual citizenship in 200 countries from 1960 to 2013. The database was compiled by Maarten Vink, Gerard-Rene de Groot and Chun Luk of the Maastricht Center for Citizenship, Migration and Development (MACIMIDE) at Maastricht University.

Provides information about the extent to which national citizenship laws provide sufficient protection against statelessness, based on the relevant international legal standards, such as those of the 1954 Convention Relating to the Status of Stateless Persons and the 1961 Convention on the Reduction of Statelessness.