Renewed public and policy concerns across most industrialised nations about food safety and public health - e.g. those focused on GM food crops - make the growth of sociological interest in food timely. The main aim of this paper, is to provide an introductory survey of "the sociology of food". A subsidiary aim takes the case of GM to illuminate the limitations of this field and to suggest that, in order to characterise the topic in adequate sociological terms, a bridge is needed to the different field of "agri-food theory", thus encompassing the whole food chain. A brief review of the interlinking of UK supermarkets and New Zealand food exporters provides the background to our argument that, in respect of events surrounding GM, supermarkets have to be seen not just as "producers" in the retail part of the supply side, but also as regulators/ auditors and even "consumers" in the food chain.