Mechanisms to engage lay citizens in science and technology are currently in vogue worldwide. While some engagement exercises aim to influence policy making, research suggests that they have had little discernable impacts in this regard. We explore the potentials and challenges of facilitating citizen engagement in nanotechnology from the “topdown,” addressing the following questions: Can academics and others within institutions initiate meaningful engagement with unorganized lay citizens from the top-down? Can they facilitate effective engagement among citizens, scientists, and policy makers (...) while building citizen engagement capacities? Is it possible to create independent bottom-up citizen engagement in scientific and technological issues from the top-down, and what are the challenges in doing so? Our experiences show that although academics can build citizens' individual, collective, and political capacities to engage with each other, scientists, and policy makers, this work is enormously time and energy intensive, and institutional support is needed to sustain it. (shrink)