This volume gives an integrated summary of the science related to the four giant planets in our solar system. It is the result of an ISSI workshop on "A comparative study of the outer planets before the exploration of Saturn by Cassini-Huygens" which was held at ISSI in Bern on January 12-16, 2004. Representatives of several scientific communities, such as planetary scientists, astronomers, space physicists, chemists and astrobiologists have met with the aim to review the knowledge on four major themes: (1) the study of the formation and evolution processes of the outer planets and their...