In this part’s first chapter (chapter 9), Anne Peters argues that the traditional trinity of Global Constitutionalism can and should be extended to cover a fourth, a social limb. Just as national constitutionalism has embraced the social question, Global Constitutionalism must do so too in times of globalisation fatigue. Here, Global Constitutionalism can build on and promote important trends in the post 2015-international legal order, notably the emerging cross-border social responsibility for individuals. The study of inter- and transnational social law standards and entitlements through the lens of Global Constitutionalism facilitates cross-fertilisation between social and liberal constitutional principles and works against playing out those dimensions against each other in a false competition. By absorbing the social question, global constitutionalism can mitigate its neo-liberal tilt and is rescued from being reduced to a project to deepen the power of capital and to extend a market civilisation in which the transnational investor is the principal political subject. With such a renovation from within, Global Constitutionalism can form part of a fresh ‘post-neoliberal imagination’ of international law.