Motivated by recent increases in water pollution in major US agricultural watersheds and by the shortcomings of government programs to control non–point source pollution, this paper examines the prospects for using product certification (ecolabeling) and business-to-business supply chain standards for environmental protection in commodity crop production. We introduce the sources of demand for certification and supply chain standards and the political and economic context in which they have expanded since the 1990s. We explore how various agrifood certification and supply chain standards have been used to achieve changes in production methods and/or in product attributes to meet social goals, and we discuss the prospects for applying these models to commodity crops. We conclude that the nature of corn and soybean production, distribution, and consumption—with numerous sales outlets and invisible consumption as part of processed foods and other products—makes certification schemes to limit agricultural pollution unrealistic and supply chain standards extremely challenging.