Exploring alternative economies and subaltern knowledge derived from waste: Insights from an ethnographic study of Traperos de Emaús-Navarra, Spain

•Alterity applied to a waste: economic, environmental, and epistemological dimensions.•The case reveals the importance of subaltern knowledge for sustainability transitions.•Political ecology on waste helps identify initiatives outside the mainstream.•The chosen waste collection case differs significantly from those in the Global South.•Environmental transition responses from subaltern sectors require research attention. This article explores the usefulness of the notion of alterity in waste management through a case study of Traperos de Emaús-Navarra, a bulky waste collection and recovery initiative in Spain. Guided by the principle of distributing work among more people, the initiative pursues shorter working hours and wage equality among its >300 employees. Drawing on this experience, the article explores alterity from three perspectives: an economic perspective centred on practices associated with the social and solidarity economy, an environmental perspective rooted in political ecology on waste, and an epistemological perspective focused on the recognition of subaltern practices and knowledge. This text contributes to sustainability transitions research by highlighting the knowledge and practices of subaltern actors that are typically overlooked by the hegemonic focus on eco-efficiency.