Over the past decade, the private sector has rapidly built up an array of private food standards to assure quality and safety in a fiercely competitive market. These private standards have sometimes been to fill in for missing public standards, especially for safety, and to differentiate products and build reputation, for both quality and safety. Moreover, private standards are increasingly related to meta-management systems assuring both quality and safety at all levels of a chain, enforcing and certifying the implementation of process standards. The privatization of standards has been important for both buyers and suppliers in the chain. They tend to be formulated and imposed by buyers (retailers and processors), and are key to their cost control and reputation with consumers, thus overall competitiveness. They are imposed on suppliers, who often find that the standards imply very substantial outlays for reporting, new equipment, and training. The lucky - a relatively small subset of the original set of suppliers - tend to find that meeting the standards, with formal certification in hand, benefits their business, opens new opportunities. The excluded tend to find themselves relegated to waning and unprofitable markets. The above points concerning the determinants and effects of the formulation and implementation of private standards are illustrated with cases from the dairy, coffee, wheat products, and coconut product chains in Brazil.