A wealth of scientific evidence, technological advances and marketing strategies support our current claim to know a great deal about the history of a product of animal origin, about its quality and even about the risks it poses for consumer health. Thousands of documents, readily accessible online, and countless electronic databases in Universities and R&D centres contain information on traceability methods, serve as a basis for legislation in this area, and provide guidelines regarding the potential implementation of such methods in the livestock industry. Nevertheless, scientists involved in animal production in general, and animal feeding in particular, must recognise – and duly inform legislative authorities – that current knowledge is not yet sufficient to guarantee the total traceability of products of animal origin. One major factor preventing the total tracing of livestock products through the food supply chain is a lack of knowledge regarding the traceability of the feed consumed by the animal. The COST Feed for Health Action, with which the speaker is involved, aims – among other things – to acquire greater knowledge in this field. The present paper seeks to foster scientific discussion of the concept of Feed Traceability, and to review state-of-the-art technologies that might contribute to the implementation of feed traceability mechanisms in livestock production systems.