CITIZENSHIP AND STATELESSNESS IN THE MEMBER STATES OF THE SOUTHERN AFRICAN DEVELOPMENT COMMUNITY 2020 the soil), whereby an individual obtains citizenship because he or she was born in a particular country; and jus sanguinis (law or right of blood), where citizenship is based on descent from parents who themselves are citizens. A variant on the jus soli principle is the concept of “double jus soli”, whereby a child born in a country of at least one parent also born there is attributed nationality at birth. In general, a law based only on jus sanguinis will tend to exclude from nationality residents of a country who are descended from individuals who have migrated from one place to another. An exclusive jus soli rule, on the other hand, would prevent individuals from claiming the nationality of their parents if they had moved away from their “historical” home, but is more inclusive of the actual residents of a particular territory. In practice, another distinction is often more important in citizenship law, between citizenship attributed at birth and citizenship that is acquired later in life on the basis of an application that is founded on a strong connection to the country. Citizenship laws thus also provide for an adult to be able to acquire nationality (through procedures variously termed registration, naturalisation, option, or declaration) based on criteria that usually include long-term residence and marriage, but may also include other grounds such as birth and/or residence during childhood. This distinction between “attribution” of nationality (automatic, by operation of law) or “acquisition” of nationality (based on an application) is explicit in the language used in the laws of the civil law countries. In the common law tradition, however, “acquisition” is often used to cover both attribution at birth and later acquisition on the basis of an application. The terms will here be used as they are in national law. In many countries, the rights of those who are citizens from birth or who have acquired citizenship later are the same; but others apply distinctions, especially in relation to the holding of public office. In addition, citizenship acquired on application may usually be more easily withdrawn. ix UNHCR / December, 2020