Book excerpt: Concern about health effects from exposure to pesticides in foods is growing as scientists learn more about the toxic properties of pesticides. The Delaney Clause, a provision of the Food, Drug and Cosmetic Act, prohibits tolerances for any pesticide that causes cancer in test animals or in humans if the pesticide concentrates in processed food or feeds. This volume examines the impacts of the Delaney Clause on agricultural innovation and on the public's dietary exposure to potentially carcinogenic pesticide residues. Four regulatory scenarios are described to illustrate the effects of varying approaches to managing oncogenic pesticide residues in food.