A Comparative Study of the Outer Planets Before the Exploration of Saturn by Cassini/Huygens: Introduction -- Formation and Evolution of the Giant Planets -- Formation of the Outer Planets -- Formation and Composition of Planetesimals -- Formation of the Cores of the Outer Planets -- Structure and Evolution of Giant Planets -- Formation of Giant Planets — An Attempt in Matching Observational Constraints -- Neutral Atmospheres of the Giant Planets and Their Satellites -- Neutral Atmospheres of the Giant Planets: An Overview of Composition Measurements -- Coupled Clouds and Chemistry of the Giant Planets — A Case for Multiprobes -- Comparative Study of the Dynamics of the Outer Planets -- Photochemistry in Outer Solar System Atmospheres -- Formation and Evolution of Titan’s Atmosphere -- Aerosols on the Giant Planets and Titan -- The Changing Face of Titan’s Haze: Is It All Dynamics? -- Io’s Atmosphere and Surface-Atmosphere Interactions -- Aurorae and Magnetospheres -- Solar System Magnetospheres -- The Current Systems of the Jovian Magnetosphere and Ionosphere and Predictions for Saturn -- Giant Planet Ionospheres and Thermospheres: The Importance of Ion-Neutral Coupling -- Energetic Particles in the Magnetosphere of Saturn and a Comparison with Jupiter -- Radio Wave Emission from the Outer Planets before Cassini -- Satellites and Rings -- Geology of the Icy Satellites -- Triton, Pluto, Centaurs, and Trans-Neptunian Bodies -- Irregular Satellites in the Context of Planet Formation -- Dynamics and Composition of Rings -- Exo-Astrobiological Aspects of Europa and Titan: From Observations to Speculations.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 satellites, beginning with the formation of compounds and planetesimals in the solar nebula, and the subsequent evolution of the interiors of the outer planets, (2) a comparative study of the atmospheres of the outer planets and Titan, (3) the study of the planetary magnetospheres and their interactions with the solar wind, and (4) the formation and properties of satellites and rings, including their interiors, surfaces, and their interaction with the solar wind and the magnetospheres of the outer planets. Beyond these topics, the implications for the prebiotic chemical evolution on Europa and Titan are reviewed. The volume is intended to provide active researchers in the fields of planetary and solar system science, space plasma physics, and astrobiology with an up-to-date status report on the topic, and also to serve graduate students with introductory material into the field. At the time of publication of this book, the study of the outer planets is particularly motivated by the fact that the Saturn system is being investigated by the Cassini-Huygens mission. Reprinted from Space Science Reviews, Volume 116, Nos. 1-2, 2005.