The International Space Science Institute (abbreviation: ISSI) is an Institute of Advanced Studies based in Bern, Switzerland. The work at this institute is interdisciplinary, focusing on the study of the solar system, and encompasses planetary sciences, astrophysics, cosmology, astrobiology, and the Earth sciences. A main activity is the interpretation of experimental data collected by space research missions.
ISSI is a non-profit organization and a foundation under Swiss law, it was set up in 1995. Its operations are supported by grants from the European Space Agency, the University of Bern, the Swiss Confederation and the Swiss National Science Foundation (SNF)