1. Introduction This study explores the situation of statelessness in Cambodia. It does so by identifying and examining the scope and conditions of specific populations who are stateless or at risk of statelessness. Such a ‘mapping’ of statelessness has been conducted in other countries but has so far been lacking for Cambodia. The question of who is stateless is elementary for understanding the scope and scale of statelessness in Cambodia. This mapping study was finalised in the year marking the 70th anniversary of the 1954 Convention relating to the Status of Stateless Persons (‘1954 Convention’). According to Article 1(1) of the 1954 Convention, a stateless person is someone ‘who is not considered as a national by any State under the operation of its law’.1 This definition requires consideration of the law as it is written and how it is applied in practice. The latter is particularly relevant for this study on Cambodia. The UNHCR, the focal agency on statelessness within the UN system, published a Handbook on Protection of Stateless Persons that sets out further guidance on interpreting this definition.2 The present report uses the term stateless persons in this sense and focuses on stateless persons falling within this definition. The terms ‘nationality’ and ‘citizenship’ are used interchangeably in this report. Well-known difficulties exist with identifying stateless persons and estimating the number of affected people and communities that are often socially marginalised. This is true more generally, but additional challenges exist in Cambodia which has so far not officially recognised the existence of stateless persons on its territory and therefore does not identify or systematically collect data on such populations. International Recommendations on Statelessness Statistics (IROSS) have been designed to address this global challenge, but these are not yet widely implemented.3 Due to these difficulties, this study also takes account of persons of unknown or undetermined nationality, who may be at risk of statelessness. For years, Cambodia did not appear in the UNHCR’s international statelessness statistics. In 2018 for the first time, Cambodia was listed with 57,444 persons falling under the organisation’s statelessness mandate, including those with undetermined nationality. This figure 1 Convention relating to the Status of Stateless Persons (1954), Art. 1. <https://www.ohchr.org/en/ instruments-mechanisms/instruments/convention-relating-status-stateless-persons> 2 UNHCR (2014) ‘Handbook on Protection of Stateless Persons’. <http://www.refworld.org/ docid/53b676aa4.html> 3 Expert Group on Refugee, IDP and Statelessness Statistics (2023) ‘International Recommendations on Statelessness Statistics’, UN Statistical Commission, Decision 54/121.<https://egrisstats.org/ recommendations/international-recommendations-on-statelessness-statistics-iross/>