This chapter describes how philosophical theorizing about justice can be connected with empirical research in the social sciences. We begin by drawing on some received distinctions between ideal and non-ideal approaches to theorizing justice along several different dimensions, showing how non-ideal approaches are needed to address normative aspects of real-world problems and to provide practical guidance. We argue that there are advantages to a transitional approach to justice focusing on manifest injustices, including the fact that it enables us to set (...) aside some reasonable disagreements about justice. The ‘bottom-up’ approach we advocate, for which we borrow Wolff’s term ‘real-world political philosophy’, is an empirically-informed normative analysis that attends to specific, identifiable injustices, and thus is partial, though not isolationist. We illustrate our approach by considering how different models of the nature of disability suggest different kinds of remedy for injustices faced by persons living with disabilities. We reflect on the nature and significance of vulnerabilities, and we assess the role of public opinion in normative theorizing, suggesting a particular significance for the opinions and experiences of marginalized groups. We finally reflect on the relevance of European legal and institutional frameworks for theorizing justice in Europe. (shrink)