In this innovative study based on the basic principles of transnational citizenship law and the naturalization pattern around the world, Matias purports that it is possible to determine that no citizen in waiting should be permanently excluded from citizenship. Such a proposition not only imposes a positive duty overriding an important dimension of sovereignty but it also gives rise to a discussion about undocumented migration. With its transnational law focus, and cases from public international law courts, European courts and national courts, may be applied to virtually anywhere in the world.