Can popular organizations engage with the state in a lasting collaborative interaction that benefits their interests without being politically co-opted or captured? This article addresses this question by analyzing the interaction between cartonero organizations and the PRO administrations in Buenos Aires City between 2002 and 2018. It shows how cartoneros managed to prompt a change in the PRO’s policies on recyclable waste collection. The article’s main arguments are that popular organizations’ opportunity to gain formal access to the state without losing their autonomy is related to the strategic orientations of both the popular organization and the ruling party, and that such a possibility increases when the popular organization is not part of the incumbent party coalition. The “troubled collaboration” between cartoneros and the PRO was possible due both to the cartoneros’ combination of contentious and institutionalized actions and to an important change in the PRO’s strategic orientation toward cartoneros.