This collection of essays comes from the international project "Science and Democracy". It offers an examination of several controversial issues, within and about science, of wide-ranging social relevance. A partial list runs as follows: the role of scientific technology in shaping our life; the influence of corporations on contemporary medicine; grass-roots activism and new technologies; environmental constraints on economical growth; the HIV/AIDS controversy; the Wakefield trial and the MMR vaccine-autism link; the organ transplant ideology and business; the debate on the terrorist attacks in USA of September 11, 2001; the role of whistleblowers in science; etc. - Contributions by J. Barretto Bastos Filho, H. Bauer, M. Brown, M. C. Danhoni Neves, F. Fabbri, P. Ghisellini, S. Lang, A. Liversidge, C. Loré, M. Mamone Capria, R. Maruotti, D. Mastrangelo, S. Maurano, M. Mazzucco, D. Rasnick, S. Siminovic, S. Ulgiati, M. Walker.