This paper analyses the recent widespread moves to 'restore' public trust in science by developing an avowedly two-way, public dialogue with science initiatives. Noting how previously discredited and supposedly abandoned public deficit explanations of 'mistrust' have actually been continually reinvented, it argues that this is a symptom of a continuing failure of scientific and policy institutions to place their own science-policy institutional culture into the frame of dialogue, as possible contributory cause of the public mistrust problem.