Ireland’s Migrant Integration Strategy 2017-2020 states that the introduction of both civics and language tests for those seeking citizenship in Ireland will be examined. This research aims to contribute by investigating requirements linked to naturalisation in Europe. Drawing on a wide range of sources, including a related European Migration Network study, a mapping exercise was undertaken across 27 EU Member States and the UK. Case studies on Belgium, Finland, Portugal and the UK, as well as on three English-speaking countries outside of Europe, were compiled. The research finds that 24 Member States plus the UK require naturalisation applicants to show language proficiency. National practices and the level of competence required varies widely. 18 Member States plus the UK require applicants to show civic knowledge or proof of integration, again with much diversity in practices found.