The equitable use and distribution of shared water resources is a topic of renewed regional debate in Latin America, especially given the recent review of the Binational ITAIPU Treaty between Brazil and Paraguay. Building more equitable and transparent agreements in this context requires an understanding of the historical trends of negotiations. This study analyzes five decades of negotiations on the shared use of water resources in the Paraná River Basin, drawing on interviews with former negotiators and officials from Argentina, Brazil, and Paraguay. The complex interaction between internal dynamics and geopolitical factors in establishing state-owned transboundary hydroelectric plants is highlighted. Based on these findings, we propose a conceptual framework that identifies the key elements to consider when negotiating strategic resources at national and regional levels. This study, extending beyond the Paraná basin, offers an applicable model for managing other shared natural resources, providing useful insights into negotiation strategies for transboundary resource and infrastructure management.