U.S. corn farmers are among the most productive and technologically advanced in the world, generating a record harvest of nearly 14 billion bushels in 2013—enough corn to fill a freight train longer than the circumference of the Earth. This production supports a mammoth agricultural sector comprised not just of farmers, but also major food, feed and energy companies that have an enormous stake in the long-term productivity and resilience of American agriculture. However, in the face of this bounty, three major threats to U.S. corn production loom: climate change, unsustainable water use and inefficient and damaging fertilizer practices. This report provides new data and interactive maps on the risks facing U.S. corn production, as well as detailed recommendations for how corn-buying companies and their investors can catalyze more sustainable agricultural practices that will reduce these risks, preserve and enhance yields, and protect precious water resources.