Over the last few years, the European Commission has repeatedly emphasized that, in the face of global uncertainty, the EU has to strengthen its social dimension and foster better working and living conditions for its citizens. To achieve this, the EU wants to strengthen social citizenship by advancing social rights, implementing the principles in the European Pillar of Social Rights at both the European and national level. The overarching objective of the EuSocialCit project, of which this paper is part, is to examine the state of EU social citizenship as well as possible policy scenarios that may strengthen it. This prompts initial foundational questions for the project: what is the nature of EU social citizenship and the social rights associated with it? And, what is the rationale for the EU to be involved in providing social rights? In order to understand the state and nature of EU social citizenship and the role that the EU plays in this now and in the future, we believe that it is necessary to ‘dissect’ the constitutive elements of social rights at the various levels (local, national and EU) at which they are provided. To this end, this paper develops a resource-based and multi-level conception of social rights. With regard to the rationale, we offer an overview of the main approaches that prevail in the long-standing debate on the justification and feasibility of a stronger EU social citizenship and present a synthesis of these approaches that may help further the debate.