The Salween River is one of the last free-flowing transboundary rivers in Asia, shared by China, Thailand, and Myanmar. This culturally diverse and biodiversity-rich river holds ample hydropower potential and has been under pressure for development in recent decades. Balancing developmental pressure and sustainability is a key challenge in water diplomacy concerning the Salween basin. This chapter outlines existing water interactions in the Salween basin at the international and subnational levels involving governments, state-owned enterprises, and civil society actors. These multi-scalar water interactions also present various potential entry points for water diplomacy that can contribute toward enhanced environmental sustainability and social justice. International experts, transnational civil society, and conflict mediators have important roles to play in the Salween basin in advancing international cooperation among government, state-owned enterprises, and local civil society.