Almost two-thirds of all irrigated U.S. agricultural acreage relied on groundwater as a primary or secondary source of water in 2018, according to data from USDA’s National Agricultural Statistics Service (NASS). The shared nature of many groundwater resources means pumping by one irrigator affects water availability for nearby irrigators. That connectivity led to the creation of groundwater management districts, natural resource districts, groundwater sustainability agencies, and other groundwater management entities. These organizations play a critical role in determining the future of groundwater-based irrigated agriculture, but national data about their functions has only recently become available.