After a series of decisions, the Court of Justice of the EU has been accused of undermining the value of Union citizenship as a tool to overcome the confines of ‘market citizenship’, thereby conferring residence and equal treatment rights to all Union citizens, regardless of economic status. This chapter argues that, rather than ‘abandoning’ Union citizenship, the Court has evolved its approach in these cases following the adoption of Directive 2004/38. The Court treats residence and equal treatment rights under the Directive as a closed system, with lawful residence under Article 7 of the Directive being the gateway to citizenship rights. Whilst this is legally coherent, strict reliance on the Directive is liable to create problems, particularly for low-wage workers and the economically inactive. The closed system of residence and equal treatment rights potentially results in more insecurity when (i) Member States systematically check the individual’s residence status when assessing social assistance claims; (ii) the individual applies for permanent residence status and must prove lawful residence for a continuous period of 5 years; and (iii) returning to their home Member State with a third country national spouse following a period of residence in a host Member State.