Nationality at birth derives from a Yemeni father regardless of place of birth; birth in Yemen alone does not confer citizenship, with a limited safeguard for children of unknown or stateless fathers.
A child of a Yemeni father acquires Yemeni nationality automatically regardless of birthplace; the mother transmits nationality only where the father is unknown, stateless, or of unknown nationality.
Ordinary naturalization requires about ten years of continuous lawful residence plus good character, Arabic knowledge, and lawful income (reduced to about five years for persons of Yemeni origin); grant is discretionary.