This article moves past high politics and the most prominent activists to explore the daily, intimate practice of international movement building by mid-level fieldworkers within the International Planned Parenthood Federation (IPPF) during its first decade of existence (1952–62). It illustrates how fieldworkers and the IPPF’s practitioner-oriented newsletter Around the World attempted to bridge the ideological and geographic diversity of the family planning movement and connect with advocates around the world through an emotive narrative of suffering, love, and global humanity, reinforced by affective bonds and women’s volunteerism. The story of global family planning must thus be seen not only as part of the history of eugenics, population control, and feminism, but also as part of the longer trajectory of maternalist humanitarianism. This mid-twentieth century version of maternalist humanitarianism built on earlier traditions but also incorporated concepts of human rights, critiques of dominant gender and sexual norms, and an official commitment to local self-determination in the context of decolonization movements. Still, the organization was plagued by the problems that shape humanitarianism more broadly, including the difficulty of moving past colonialist discourses, deeply rooted feelings of racial superiority, and the contradictions inherent in attempts to impose an impossible ideal of political neutrality in a politically complex world. Looking at the history of global family planning from this perspective thus helps us understand how the different traditions, intimate relationships, and practical experiences mid-level actors bring to their work shape the broader process of international movement building, beyond high-level political and ideological activism.