The Food Waste program explores the causal factors and economics of food loss in food systems. Food Waste is a critical weakness in food systems, and our work aims to identify best practices and solutions for minimizing food loss. The causes of food waste or loss are numerous and occur at all stages of the food supply value chain: production, transportation, processing, retailing and consuming. In low-income countries, most loss occurs during production. In developed countries an estimated 100 kilograms (220 lb) per person per year is wasted at the consumption stage. Globally, food loss and waste amount to between one-thirdand one-half of all food produced.