This chapter focuses on the role of institutions in facilitating treaty effectiveness. It discusses the importance of international agreements in promoting and sustaining cooperation. It considers treaty design to further reflect on the type of treaties, and the various mechanisms stipulated in these agreements, that contribute to treaty effectiveness by assuaging conflict in situations of water scarcity and increased variability. The chapter argues that the design of a treaty seems particularly relevant in regions where climate change and water variability could impact the ability of basin states to effectively manage shared water. The chapter demonstrates how various mechanisms such as different water allocation mechanisms, as well as additional stipulations, such as, side-payments, issue-linkage, benefit-sharing, adaptability, and information exchange, affect the performance of the treaty in the context of water scarcity and variability. These mechanisms are examined from an empirical and large-n perspective, assessing how treaties with such mechanisms fare compared to treaties devoid of these mechanisms.