This volume focuses on isotopic signatures of volatile elements as tracers for evolutionary processes during the formation of the Sun and the planets from an interstellar molecular cloud and, in turn, illuminates how the isotopic compositions of the present-day solar system objects have been established. The book is an integrated collection of articles by experts in planetary science, solar and plasma physics, astrophysics, mineralogy and chemistry that met for an interdisciplinary workshop at the International Space Science Institute in Bern in January 2002. The authors present analyses of isotope abundance ratios for volatile elements in the sun, planets, satellites, comets, meteorites and interplanetary dust particles, as well as a review of isotopic ratios in star-forming interstellar clouds. This provides insight into the physical and chemical processes in the pre-solar molecular cloud that collapsed to form the Sun and the solar accretion disk.