This report relies on fi ndings from several national surveys and current literature to assess water resource use and conservation measures within the U.S. irrigated crop sector. U.S. agriculture accounts for 80-90 percent of the Nation’s consumptive water use (water lost to the environment by evaporation, crop transpiration, or incorporation into products. Expanding water demands to support population and economic growth, environmental flows (water within wetlands, rivers, and groundwater systems needed to maintain natural ecosystems), and energy-sector growth, combined with Native American water-right claims and supply/demand shifts expected with climate change, will present new challenges for agricultural water use and conservation, particularly for the 17 Western States that account for nearly three-quarters of U.S. irrigated agriculture. Despite technological innovations, at least half of U.S. irrigated cropland acreage is still irrigated with less effi-cient, traditional irrigation application systems. Sustainability of irrigated agriculture will depend partly on whether producers adopt more effi cient irrigation production systems that integrate improved onfarm water management practices with effi-cient irrigation application systems.