Abstract How does the public articulate its visions, expectations and concerns regarding a technology whose applications and ramifications are only just beginning to be worked out? Nanotechnology is an emerging technology on the brink of offering transformative applications to the food industry at every level, from food packaging to the nutritional quality of the food itself. But the very newness of the field has had a significant impact on efforts to establish a dialogue between scientists and the general public on issues surrounding the commercialization of nanotechnology. In such a context, facilitating a dialogue between scientists and the general public is a formidable task, and yet the idea of “upstream engagement” is gaining currency as an approach that may alter the present relationship between science and society. A series of critical questions arise. Will attempts to engage citizens in discussions of nascent technologies empower them? How will such attempts ultimately address the normative commitment of science and technology studies to the democratization of scientific and technological decision making? How do lay participants in such dialogues negotiate the differences in expertise between themselves and scientists? How do they establish the legitimacy of their assertions? How do nonscientist members of the public evaluate statements made by both scientists and nonscientists? The study offers a critical analysis of an experimental attempt at upstream engagement in the Japanese context and the social dynamics which hinder meaningful dialogue.