Includes bibliographical references / This dissertation seeks to explore the core drivers of international cooperation over shared water courses particularly in Southern African, using the example of the Okavango River Basin as a case study. As a starting point it highlights the hydro-political context of Southern African, which is dominated by more than 21 shared water courses and faces significant challenges to its water sector namely through climate variability and population growth. In light of these pressing issues which could create a security complex for sovereign riparian states, international cooperation over trans-boundary water sources is imperative. Drawing on core theories of international relations, this dissertation suggests that cooperation between riparian states is a result of strong institutional frameworks, at a river-basin, regional and international level. Cooperation is further reinforced through development functionalism which plays an important role in facilitating cooperation through the advancement of regional development goals and initiatives. Finally, the dissertation explores the role of international norms of cooperation over trans-boundary water courses and the important role they play in fostering cooperation. Using the case of the Okavango River Basin, the dissertation suggests that in Southern Africa, the strongest driver of cooperation is strong legal and institutional frameworks, which once established, form the basis for sustainable cooperation for water diplomacy between riparian states. Cooperation over the Okavango River Basin and the twenty years of cooperation established between Angola, Namibia and Botswana through the Permanent Cubango-Okavango River Basin Commission (OKACOM) highlights an optimistic account for hydro-political cooperation over trans-boundary water systems between sovereign riparian states and provides a useful model for water basin agreements that are yet to be established. This thesis thus concludes that in light of the growing challenges facing the water sector in Southern Africa, strong institutions and legal frameworks are required to enhance cooperation among riparian states.