Technical Abstract: To support the Agricultural Research Service¿s Conservation Effects Assessment Project (CEAP) in assessing USDA conservation programs and practices on soil and water quality, a publicly available web-based watershed data system, called Sustaining the Earth¿s Watersheds, Agricultural Research Data System (STEWARDS), was developed to provide data search, viewing, and downloading of watershed research data. The data system organizes and documents soil, water, climate, land-management, and socio-economic data from multiple watersheds across the US. This paper describes the STEWARDS data contained within the system, user interface, and how it would deliver watershed data. STEWARDS is a data delivery system with a GIS interface, using space, time, and topic as the key fields for searching the extensive ARS watershed data. Through this interface, the system will facilitate 1) researchers in obtaining ARS¿ historic watershed data for hydrological studies; 2) modelers in retrieving measured data over extensive time periods for model calibration and validation in watershed assessments to support the conservation effects assessment program; and 3) watershed managers and a wide array of partners and stakeholders in accessing long term data to support decision-making for selecting effective conservation practices.