Water is increasingly recognized as a scarce resource that must be managed more efficiently than in the past. In addition to physical scarcity, the cost of accessing these resources is climbing. This publication explores institutional frameworks in three case studies of long-standing and successful water markets. These cases demonstrate the common features and essential elements of water markets. They also show how to design markets that consider the local institutional, social, and political conditions and how to integrate those markets into existing water resource management arrangements. The papers are written for practitioners interested in how water markets operate, for decisionmakers faced with the challenge of selecting a water resource allocation system, and for academics interested in analytical-descriptive case studies that provide information on how to conceptualize the functioning of water markets from an institutional perspective.