Some view ILO conventions as ‘labour standards’ that set norms on worker rights but not ‘human rights’ standards; others see them as human rights guarantees. This chapter pinpoints the gradual shift of debate on this issue, and the change in attitudes in the ILO itself. At the ILO’s founding in 1919, the concept of ‘human rights’ was unknown (or at least not expressly articulated as such); rather, pursuing ‘social justice’ for workers was the mission of the ILO. In 1944 with the Declaration of Philadelphia, the ILO adopted a rights-oriented approach. Since the 1990s, an era of increasing globalization, the UN system has accepted that economic development without corresponding acceptance of human rights is not sustainable, which aligns with the ILO’s long-time belief that ‘there can be no lasting peace without social justice’. In 1998 when the ILO adopted its Declaration of Fundamental Principles and Rights at Work, it proclaimed openly for the first time that the ILO dealt with human rights, and the UN since then has acknowledged that fundamental labour rights are human rights.