Fundamental changes are underway in the U.S. agri-food system, changes that are altering traditional marketing relationships. Parts of the food system are becoming tightly integrated, such as the poultry subsector and, increasingly, the pork subsector. The tightening of vertical linkages has been characterized by movement from open markets to various forms of managed coordination, e.g. contracting, strategic alliances, and single ownership of multiple market stages. 1998 AAEA Symposium