The Mekong River in Southeast Asia is an important source of life for people living within the basin. Sharing the river’s water resources is, however, becoming increasingly difficult, and has already sparked disputes among riparians. Climate change could potentially increase political instabilities and intensify interstate disputes. This policy brief therefore argues that it is important to increase capacities to adapt to changing climatic conditions. Synergies between climate and water diplomacy should be harnessed in order to overcome existing shortcomings and improve adaptive capacities.