Nanotechnologies and the Converging Technologies Programmes (CT) put forward relevant challenges to the governance of science and technology, because their development takes place in the context of a transnational R+D+i system with a plurality of competitive and cooperative agents who pursue a diversity of goals. How to integrate the plurality of technoscientific agencies and how to establish the research priorities of CT Programmes constitute significant problems. This paper presents a comparison between the American (NBIC) and European (CTEKS) CT programmes in order to analyse their commonalities and differences. It is argued that nanosciences and nanotechnologies constitute one of the main instances of contemporary technoscience, assuming the thesis that in technoscience (contrary to what happens in traditional science), scientific knowledge is not and end in itself, but just an instrument to obtain social, political, economic or military ends. Then, it is proposed a general philosophical hypotesis about the colonization and industrialization of the nanocosmos, and the notion of scientific agenda is put forward in order to analyse and characterise the diverse models of governance.