This chapter argues that “solidarity” should be understood as being “unbound” by geographical or temporal borders. As such solidarity can be inclusive, involving collective action and worker voice, engaging empathy rather than merely shared identity. In this way, connections are made between solidarity and sustainability, which entails cross-border intra-generational and inter-generational commitments as well as activity by civil society, including trade unions, for its realization. In this context, the chapter examines the United Nations Sustainable Development Goals adopted in 2015, identifying their recognition of inclusive solidarity in the context of decent work and their potential limitations. The influence of these aspirations on the European Pillar of Social Rights 2017 is also considered, alongside the ways in which the Pillar and (indirectly) the SDGs are being translated from a form of soft law into harder EU legislative forms. In this respect, the European Commission’s new policy agenda for 2020 is interrogated. It is argued that there is scope for transnational (unbounded) worker solidarity to be actualized through a sustainability agenda instantiated into both soft and hard EU law, but its realization is some way off.