AbstractWhile the circular economy (CE) is discussed in the global North as an innovative approach to waste management, the idea of circular resource flows has long been central in the work of waste pickers all over the world. They work independently or in groups, collecting, classifying, and reinserting a wide range of discarded materials into the economy. These grassroots initiatives have accumulated valuable knowledge and offer innovative perspectives on handling waste, informed and framed by their everyday experiences. Yet their efforts are hardly recognized as contributions to the circular economy, nor are most of the services they provide remunerated. Despite their precarious working and living conditions, waste pickers provide a specialized workforce, proven to be efficient in the reclamation of discarded and wasted materials, in reverse logistics such as extended producer responsibility (EPR) and service contracts involving municipalities and industries. With some exceptions, the organization of human labour that underpins the circular flows of matter and energy is an absent analytical dimension in most of the literature in this field. The dominant CE concept focuses primarily on environmental and ecological sustainability outcomes but lacks attention to social sustainability and livelihood aspects. Our paper bridges this gap in the literature by discussing results of qualitative research conducted in the metropolitan regions of São Paulo, Brazil, and Buenos Aires, Argentina, in 2017 and 2018, illustrating how waste picker organizations provide selective waste collection services to communities and businesses and thus contribute to resource recovery and social inclusion, at the heart of the CE.