A citizenship-acquisition concept defining eligibility, procedures, and adjudicative steps for obtaining or changing citizenship status. It governs residence, character, testing, and oath requirements or formal processes for relinquishing citizenship status. It does not confer citizenship absent completion of required adjudication steps and does not excuse disqualifying conduct or ineligibility. It determines the legal status of citizenship and the rights and obligations associated with that status. The concept is generally stable, though procedures and interpretive standards may be updated over time.