This article explores the way in which rules on national citizenship and rights connected to Union citizenship, respectively, contribute to affect the status of third country nationals in the European Union, and their prospects for inclusion. In particular it looks at how the rights of third country nationals are treated in relevant cases on European citizenship decided by the Court of Justice of the European Union (CJEU), and it considers recent reforms in nationality legislation in a selection of member States. The article highlights two contrasting trends, respectively, in EU case law on the relation between Union citizenship, nationality and the rights of third country nationals, and in recent member States’ legislation on admission of immigrants and access to nationality. CJEU holdings encourage the application of objective criteria for deciding on inclusion within, and exclusion from, the legal space of the member States, and tend to identify an autonomous space of inclusion and exclusion, regardless of nationality, around Union citizenship. The result is a subtle pressure towards the ripening of a Europe-wide notion of belonging. National legislation, on the other hand, leaves a measure of discretion to national authorities entrusted with deciding on inclusion and exclusion, and confirms the monopoly of the nation in inclusion and exclusion decisions. The result is a pressure to close the member States’ membership spaces around their respective individual concepts of belonging. These opposing trends reveal a dissonance between the role of Union citizenship and that of national citizenship, when it comes to the prospects of inclusion of third country nationals. Composing this dissonance requires reconsidering the weight and scope of legal categories relevant to inclusion, such as citizenship, residence, and presence.