Founded in 1919 along with the League of Nations, the International Labor Organization (ILO) establishes labor standards and produces knowledge about the world of work, serving as a forum for nations, unions, and employer associations. Making the Woman Worker illuminates the ILO’s transformation in the context of the long fight for social justice. Before 1945, it focused on enhancing conditions for male industrial workers in Western, often imperial, economies, while restricting the circumstances of women’s labors. After WWII, the ILO—then a UN agency—highlighted the global differences in women’s work, focused on bringing women into “development,” began to combat sexism in the workplace, and declared care work essential to women’s labor participation. Today, it enters its second century with a mission to protect the interests of all workers in the face of increasingly globalized supply chains, the digitization of homework, and cross-border labor trafficking. The ILO’s treatment of women provides a window into the modern history of labor. The historic relegation of feminized labor to the part-time, short-term, and low-waged prefigures the future organization of work. How we treat workers in the next century will inevitably build upon evolving ideas of the woman worker, shaped significantly through the ILO.