Rapid technological change in agricultural biotechnology, the characteristics of the technology and firms' strategic responses have altered the structure of the agricultural input supply sector and are changing vertical relationships between firms downstream in the agri-food chain. A number of economic theories shed light on what is happening, why it is happening and how the agri-food chain may evolve as a result of further technological change. Within this context, changes in the structure of downstream food and feed processing sectors are explained. The implications for vertical coordination of the segregation and identity preservation of output-trait biotechnology (products that have been modified with traits designed to appeal to specific consumer segments) are assessed.