According to available global data, around one quarter of children under the age of five have not had their births registered.13 Children are not always provided with proof of birth registration, meaning an estimated 230 million children under the age of five do not have birth certificates.14 Regional data suggests that birth registration levels in Europe are high, with estimates ranging from 98– 100% suggesting that no child under the age of five in Western Europe is without a birth certificate. 15 However, there is a lack of available, comparable and recent data in the region, and evidence from the Statelessness Index suggests that these estimates may mask some barriers to birth registration in the region.16 Analysis of the Statelessness Index data demonstrates that, whilst some countries in Europe perform well across most international norms and good practices on birth registration, there are still barriers preventing children in some countries from realising their right to immediate birth registration. Very little change has been reported in recent years among the Statelessness Index countries, suggesting that progress towards achieving universal birth registration in Europe is slow, and new challenges are emerging. Stringent evidentiary requirements, and access to birth registration procedures being conditional on parents’ residence or documentation status, as well as discrimination against LGBTIQ* families, mean that some children are prevented from having their births registered and are not being provided with a birth certificate in some countries. Fees and additional requirements, such as complex court procedures, proof of paternity or DNA testing, create further barriers to accessing free and prompt birth registration after the deadline for registration has passed. There is a critical difference between socalled registration “completeness”, a measure used by statisticians, and the achievement of Universal Birth Registration. On the UN Statistics Division website, for example, statistics only show whether countries have birth registration rates of more than 90% of vital events being registered. 16 Whilst less than 10% of births remaining unregistered may not appear statistically significant, it is essential to interrogate these statistics further to understand who is still falling through the gaps and why. The way birth registration rates are measured may also mean that some children are not captured in national birth registration data. In particular, marginalised populations are more likely to face barriers to birth registration, such as migrants and refugees, minority groups, undocumented people, or families living in areas or circumstances less likely to be captured in national household survey data, such as those living in orphanages, residential care homes or hospitals, in refugee or internal displacement camps, asylum reception centres, informal settlements, or homeless or nomadic people. This briefing uses the definition of ‘universal birth registration’ to assess countries’ law, policy, and practice, which goes beyond aggregate birth registration rates and considers the principle of nondiscrimination, in other words, whether every person is registered regardless of their race, religion, national origin, sex, or any other trait. Most countries lack formal procedures for determining whether a child has acquired a nationality in cases where they may ‘otherwise be stateless’. In some cases, countries insert an assumed nationality (or ‘unknown nationality’) at the point of birth registration or on the birth certificate, which can be difficult to change later and may mean that States are unaware or do not identify that a child born on their territory may be stateless. This has implications for the functioning of safeguards to ensure every child’s right to acquire a nationality. Laws that require health professionals and civil registry officials to report people who are undocumented or with irregular residence status to immigration authorities, as well as reports of this happening in practice in some countries where there is no such requirement, also deter parents from approaching registration authorities and hinder access to birth registration for children in migration. Due to discrimination, certain groups are disproportionately affected by barriers to birth registration including members of minority groups such as Romani people, refugees and migrants, and children of same-sex couples.