A 2006 summary of planetary rings, including results from the Cassini space mission to Saturn. It covers all aspects of the subject with particular emphasis on ring history and evolution. Basic physical processes and simple mathematical approaches are presented in a clear and accessible way, supported by many images and diagrams that display the spectacular phenomena seen in these fascinating structures. Highlighted topics include Saturn's F ring, Neptune's rings, Jupiter's rings, stochastic models, ring age and evolution, and Cassini results. The book is suitable for students and professionals in planetary science, astronomy and space research and includes the latest results, explanations and speculations. The text is supported by a glossary of terms and an extensive bibliography directs the reader to original references and resources.