Food technology has evolved from being focused on the issues associated with food availability to include, more latterly, additional foci on food safety, sustainability and functionality. Despite the intuitive appeal of these beneficial factors in providing the basis for consumer acceptance of emerging technologies applied to food production, consumer acceptance of the benefits of agri-food nanotechnology will not be automatic. Understanding consumer psychology is essential if we are to understand and predict peoples' responses to (bio) nanotechnology in the agri-food sector. A review of the socio-psychological factors influencing the societal response to novel food technologies in the past may throw some light onto the possible trajectory of the societal response to agri-food applications of nanotechnology. This chapter draws insights from past research into the psychology of novel food acceptance, novel foods and the evolution of food technology, along with current evidence from present research on agri-food nanotechnology, to identify potential barriers and opportunities for the development and introduction of agri-food nanotechnology.