Fundamental changes are underway in the U.S. food system, changes that are altering the relationships between consumers, food retailers and wholesalers, food processors and farmers and ranchers. Today's consumer — who demands an everwidening variety of healthful, conveniently prepared food products — is driving the changes in the food market. Meanwhile, advances in farm and food technology are enabling the food system to target a growing array of smaller consumer niches. Together, these changes in consumer demand and food technology are changing the traditional market structure linking consumers, processors and producers. This paper analyzes the changes taking place in the U.S. food system in three sections. The first section describes trends in food demand and food technology that underlie changes in the U.S. food system. The second section develops an analytical framework for understanding structural changes in the food system. The third section extends and refines the analytical framework to consider the food system of the future.