Policies regulating immigrants’ entitlement to public healthcare have increasingly become a sensitive issue in the public and political debate across Europe. The politicisation of healthcare access builds on anti-immigrant feelings and simultaneously fuels them, while contributing to delegitimise the role of the state in the provision of healthcare to the whole population through universalistic schemes. This chapter provides an in-depth qualitative analysis of the policies and policymaking process regulating immigrants’ healthcare access in Spain, which has variously been extended and restricted over time, thus making the case particularly appropriate to analyse policy reforms on, and the politicisation of, the health–migration nexus. As the findings suggest, these policy changes were embedded in a broader political and institutional struggle for the definition of the basic entitlement logic of the Spanish Healthcare System.