Watersheds, as integrated land and water systems, have proved difficult to manage successfully. This is in part due to the complexities of accommodating different groups of users and making use of multiple resources in spatially large areas. The paper argues, however, that watersheds have a natural physical and economic logic as a unit of analysis. As a bridge between microlevel analysis of individual farmers or economic units and a regional or sectoral approach, the watershed, when analyzed in an integrated, multi-disciplinary manner, yields useful policy results for improved management of land and water resources. Economic analysis plays a key role in this analysis. Integrated analysis, however, does not mean integrated implementation. Existing systems of social and government organization must be used to implement the chosen policies. This is a difficult, but essential step and may require the use of government fiscal and price policies to harmonize social and private goals.