Drawing on three years of ethnographic fieldwork with community composters and microhaulers in New York City, alongside the rollout of the city's curbside organics collection system, Composting Utopia describes how local, grassroots organizations intervened in the city's waste system, enacting change and presenting an alternative vision of the composting city. As Guy Shaffer argues, movement-driven infrastructure projects develop new tools for organizing the world, give communities agency over urban design, and promote just sustainability.