For more than 50 years fossil fuels and fertilizers have been the key ingredients in much greater global food production and distribution. The food-energy relationship has been a good one, but it is now entering a new era. Food production is rising sharply, requiring more carbon-based fuels and nitrogen-based fertilizers, both of which exacerbate global warming, river and ocean pollution, and a host of other ills. At the same time, many nations are grappling with how to reduce energy demand, especially demand for fossil fuels.