This paper aims to qualitatively characterize aspects of community mobilization in tackling the issue of waste in slums. This is a case study carried out in Morro dos Prazeres, in the Santa Teresa neighborhood in Rio de Janeiro - RJ, which suffered a natural disaster in April 2010, and since then, due to the lack of effective preventive actions by government authorities, faces the pressure of total removal of its inhabitants because they are in a recognized risk area. Garbage waste has been enrolled as a developer of such disasters. The method performed to characterize the community mobilization at this location was given two aspects: 1) A bibliographic and documentary research through texts published in newspapers, magazines and other communication media, public and private documents as well as technical reports already available that we had access to, having an overview of the environmental landscape, geological and vulnerability of this area to be affected by new disasters; 2) Making use of participatory research methodology and active listening, carrying out interviews and meetings in the chat-and-coffee workshops as well as informal conversations with the locals. These techniques enabled us to obtain information about the history of social mobilization at Morro dos Prazeres, about how much it contributes to the strategies of acting parties to combat the garbage waste issue and to struggle for solutions to be established as alternatives to the removal of residents. We discovered that community mobilization is a historical practice at Morro dos Prazeres. It happens since its formation in the 1940s through the exchange of culture and knowledge among its residents and their external supporters. This revelation deconstructs our initial hypothesis that the external partners, who currently work in the territory, by running a garbage recycling project based on environmental education, would have a leading role in building up mobilization that we see today about the issue of garbage waste.