The article draws upon the natural resources management model developed by economist Elinor Ostrom to examine the Constancia (Peru) mining project. It's a study of local communities’ capacity for decentralized and adaptive management within the new rhetoric of sustainable mining advanced by the companies. In what ways does this new mode of regulation allow local communities to provide for their self-organization? Do they have any influence in the very hierarchical power relations characteristic of the mining context? At issue is their ability to maintain sovereignty over their territories and manage the “Common-Pool Resources”. By taking into account the mediating role played by new professionals in the participatory process institutionalized by the state, the Peruvian legal framework offers a relevant example for analyzing the relationships of these communities with the mining companies.