Article 1 of the 1954 Convention Relating to the Status of Stateless Persons defines a stateless person as “a person who is not considered as a national by any State under the operation of its law”. Most stateless people lack access to basic socio-economic rights enjoyed by citizens (e.g., education, healthcare, the right to work, the right to own property) as well as to civil and political rights such as the right to vote. The stateless are often trapped in intergenerational cycles of poverty and vulnerability. When statelessness affects entire ethnic or religious groups within a society, it can contribute to instability, conflict, and displacement. UN Statelessness Conventions establish international standards to protect stateless people and to prevent and reduce statelessness. In most cases, statelessness is caused by nationality laws that are inconsistent with international standards, such as: laws that discriminate against certain ethnic or religious groups, preventing them from acquiring or conferring nationality; laws that limit a woman’s ability to pass her nationality to her children; and laws that provide for loss or deprivation of nationality without safeguards against statelessness. State succession can also cause statelessness if an individual’s previous State of nationality ceases to exist, or if the territory on which they live comes under the control of another State and they are not entitled to citizenship under the new citizenship law. Weak birth registration systems can also put people at risk of statelessness. While some stateless people lack citizenship because of displacement, many are stateless due to historical migration, often forced, of their parents, grandparents or earlier generations. Main messages: • There are no robust estimates of the global number of stateless people. UNHCR’s estimate of 4.2 million stateless people is based on data from 94 countries, most of which do not meet standards for official statistics. Additionally, many countries known to have substantial numbers of stateless people that do not report their statelessness situation to UNHCR. • There are three categories of stateless people defined for the purposes of official statistics. These include: (1) ‘Stateless persons’ who do not have citizenship of any country, and may be classified as stateless either through self-declaration, or through recognition by competent government authorities, on an individual or group basis; (2) ‘Persons of Undetermined Nationality’ who lack proof of citizenship but who may be entitled to nationality, and if so, could be assisted to obtain proof of citizenship by the relevant authorities; and (3) “Stateless-related people” impacted by statelessness, including formerly stateless people, children of at least one stateless parent, or people 7