We are at a crossroads when it comes to reducing the risk of adverse health outcomes from arsenic in private well water in the United States, according to Yan Zheng, Ph.D., professor at the City University of New York and community engagement leader at the Columbia University Superfund Research Program (CU SRP), and Joseph Ayotte, P.G., a U.S. Geological Survey hydrologist. They claim we have a better understanding of factors influencing arsenic occurrence in well water and its health effects but little knowledge about what actions households with private wells have taken to reduce arsenic exposure and the reasons for taking those actions.