In the first phase of the research project Nanotechnologies for Tomorrow's Society (www.nanosoc.be), the research consortium explored a variety of futuristic visions or technoscientific imaginaries. This exploration took the form of a Policy Delphi, adapted to the particular objective of jointly constructing nano-imaginaries, taking participants' personal visions of possible future applications and societal issues as a starting point. The participants were nanoresearchers, as well as societal experts and primary involved citizens. In this article, the authors describe the theoretical frame that inspired their methodological approach, present the analytical results obtained, and bring some reflections to the fore that arose as a result of the performance and analysis of this Delphi-exercise. (Contains 4 tables and 11 notes.)