Abstract Nanotechnologies, like other emergent technologies, have had mixed receptions: heightened expectations of their likely benefits are accompanied with uncertainties and fears about their potential consequences. Scientists and policymakers are acutely aware of the significance of public perceptions for the successful realisation of technologies, which is especially evident in recent policy documents and debates on nanotechnologies. Trust, or rather its absence, has been identified as a core issue of contemporary risk governance. In this context, questions regarding the ways in which risk calculations are communicated are bound to be crucial where the establishment of public support is concerned. While there has been a shift in the rhetoric of science communication, intended to signal a greater emphasis on public engagement during the early phase of technology development, the extent to which publics are currently able to shape the direction of policies affecting nanotechnology invite careful scrutin...