IAU Symposium 263 provides a state-of-the-art review of icy bodies in the Solar System, a topic crucial to understanding processes involved in the Solar System's formation, the consequences for water on planets, and ultimately, the habitable zones around other stars. Ice-rich planetesimals which form beyond the snow line are discussed, using an interdisciplinary approach. The main topics covered include: accretion of icy grains in the protoplanetary disk, the long-period comet flux and the Oort cloud population, transfer mechanisms of bodies from their source regions to the Sun's neighborhood, the physics and dynamics of trans-Neptunian objects, transition objects (comets and asteroids), cryovolcanism and modeling the interiors of icy bodies, and a review of past, present and future space missions. This volume gives a broad overview of the importance of these bodies, from comets up to liquid water on terrestrial planets, and the formation of ices in the Solar System.