Scientific communication also pertains to the domain of society, where the formation of public opinion about science and technology is taking place. Concerning this process, two main points are exposed in the commentary. The first is a proposition on how the public as a social category may be conceptualized, and the second is the extent of the participation of members of the public in strengthening socialization and democratization practices in new, highly complex, contexts of scientific research. The public is conceptualized to include all citizens no matter their professional origin, including scientists, which promotes the idea of openness and equality of the public sphere where scientific issues are discussed. To be democratic in its practical-political setting, such a conception needs to deal with the problems of participation in a highly mediatized world, where not every member of the public could be included into scientific research. The author thus reflects on the mechanisms which would enable the formation of public forums where the trust of influential public actors as stakeholders of research can be tested.