The consumption of multi-ingredient foods is increasing across the globe. Traceability can be used as a tool to gather information about and manage food safety risks associated with these types of products. The authors investigate the choice of voluntary traceability in three-tiered multi-ingredient food supply chains. They propose a framework based on vertical control and agency theory to model three dimensions of traceability systems: depth, breadth, and precision. Their analysis has three main results. First, full traceability is feasible as long as there are net benefits to a downstream firm that demands traceability across all ingredients. Second, horizontal network externalities are positive because an increase in the level of traceability in one ingredient requires a similar increase in others. Finally, vertical network effects will be positive insofar as willingness to pay and probabilities of food safety hazards increase. [EconLit Classification: Q130, L140]. r 2010 Wiley Periodicals, Inc.