If they are to tackle the huge sustainability challenge, retailers need to work with government on a single set of standards Awareness is rising rapidly in the food supply chain that it must address the sustainability challenge. But big companies, especially, are caught in a double-bind. On the one hand, retailers relish doing their own thing. On the other hand, they are so high-profile that they cannot afford to fall at the sustainability hurdle. This needs co-operation not just with each other but with the state. For consumers to be eco-citizens requires 'choice editing' by retailers. For decades, retail giants have been creating formidable systems of internal standards. They are sharing some best practice through buying consortia and spin-off bodies such as EurepGAP - now global and renamed GlobalGAP. Such standards ignore but sometimes exceed government guidance. Proof that retailers can go it alone, you might say. The problem, however, is that, supermarkets have got used to ploughing their own furrows. A bit of co-operation kicks in when needed, but nothing too serious to rock their individual and separate corporate cultures. But, as the enormity of the sustainability crisis dawns on boards, even retail giants know they cannot deliver across-the-board change needed. Hence Tesco 's new Sustainable Consumption Institute. Are retailers going to ration fuel? Or first calculate embedded carbon and then ratchet levels rapidly down? Or lead embedded water reduction in food products? The complexity is mind-boggling. Take labelling, a favoured device in neo-liberal business models. 'Let consumers make informed choices!' Hence the proliferation of voluntary labelling schemes. The labelling explosion has been in what used to be the policy fringes: animal welfare, conservation, social and labour conditions. To this list is now added carbon. There is a quiet anarchy emerging among labels. How can consumers juggle this complex data? Secondly, labelling principles veer between voluntary, mandatory and conditional. My view is that sustainability needs one comprehensive omni-standard system, which is not in fact labelling but standards harmonisation across issues, designed to ratchet them up over time. This needs state and industry co-operation globally, nationally and in the EU. The omni-standards sustainability journey must start now. n Tim Lang, Professor of Food Policy, City University t.lang@city.ac.uk