This thesis examines how groups make articulations with the Indigenous identity category of “the Diaguita Peoples” to position themselves as “consent-givers” in relation to Barrick Gold’s Pascua Lama mining project, in the Huasco Valley, in the north of Chile. I critically explore how Indigenous organisations and a mining company engage amid complex social and political changes. These changes include new environmental legislation, emerging Indigenous rights concepts, and project-related environmental impacts. Within this dynamic context, I identify how actors engage with the concept of free, prior and informed consent (FPIC) in different ways. Through analysis of legal and technical documents and ethnographic research methods in the Huasco Valley and Santiago over eight months, I explore how the Indigenous organisations organise around the identity category of the Diaguita Peoples, using Hall’s (1990, 1996) theory of articulation of identity as an analytical frame and Murray Li’s (2000) adaption of it in the context of Indigenous identity. I critically examine how groups in the Huasco Valley position themselves as “consent givers” in relation to the project and within broader relations of power to address historical grievances concerning territorial control and local economic development. The thesis shows how Indigenous organisations used FPIC to reconnect an identity of “the Diaguita Peoples” with ancestral lands. The thesis also examines the challenges for Barrick Gold’s Community Relations team as the company attempts to reconcile the new demands for recognition in the area of influence with operational pressures to move the project forward on time and within budget. While there is a large body of literature on the Pascua Lama case study, the thesis looks beyond a duality of “project proponents vs project opponents” to reveal the changing strategies of a group of Indigenous organisations in relation to the project and the demands these changes make on groups and individuals. The thesis also traces the concept of FPIC from its origins to its operationalisation in contexts requiring its “real-life” application, and the complex ways in which Indigenous groups engage with the concept of FPIC to pursue objectives beyond the direct scope of the project. The identity of “the Diaguita Peoples” is not fixed but constantly shaped, constructed and reconstructed through interactions between actors in the Huasco Valley as they make meaning of Indigenous identity through complex, and often strained relationships around the Pascua Lama project.