Unique identifiers, often in the form of a unique identification number (UIN), are critical in the management of administrative records. They provide a unified means of identification across different systems and over time, facilitating both the statistical use of administrative data and improved service delivery for individuals, along with streamlining the administrative functions of government. They are generally, the minimum requirement in the development and maintenance of administrative registers, given their ability to uniquely identify each unit in the register. Overall, benefits of unique identifiers include enabling reliable and efficient delivery of government services through improved identification and targeting of beneficiaries; strengthening linkages and preventing duplication between registers, thereby ensuring better control over data quality; reducing leakages in the distribution of welfare and social security benefits; and expanding the inclusivity of existing systems. Combining and consolidating information from multiple, separate systems or registries into a single register is both operationally efficient and cost-effective. Moreover, integrating data from multiple sources allows for cross-validation, further enhancing the accuracy and reliability of information.