INVISIBLE KIDS Childhood Statelessness in the UK Glossary Stateless person Leave to Remain ‘Stateless person’ has a legal definition in international law, which is ‘a person not considered as a national by any State under the operation of its law’. Sometimes it is unclear whether a person is stateless, and statelessness may become evident over time. Being stateless is not the same as being undocumented (see also ‘Undocumented’). Permission to stay in the UK (equivalent to temporary residence for a limited time). At risk of statelessness ‘At risk of statelessness’ does not have a legal definition. We use this term to refer to people who may not be stateless at present but may become stateless due to circumstances that can cause statelessness. Sometimes it is unclear whether a person is stateless, and statelessness may become evident over time. Nationality/Citizenship We use these terms interchangeably in this report to mean the legal bond through which a person is considered to belong to a State. Jus sanguinis Citizenship that is acquired by descent, through one’s parents. Jus soli or birthright citizenship Undocumented Citizenship that is acquired automatically by birth on a territory. A person who does not fulfil the requirements established by a host country or country of destination to enter, stay, or exercise an economic activity is defined as an ‘undocumented migrant’. The term ‘undocumented’ may also be used to refer to a person who lacks any documentary proof of their legal status in a country. Being undocumented is not the same as being stateless (see also ‘Stateless Person’). Registration Indefinite Leave to Remain Permission to stay in the UK, with no time limit (equivalent to permanent residence). One of the processes by which a person becomes a British citizen. Registration applies mainly to children and a few adults and is sometimes by entitlement and sometimes discretionary (see also ‘Naturalisation’). Naturalisation One of the processes by which a person becomes a British citizen. In the UK, naturalisation is always discretionary and applies only to adults.