Before the Institut Pascal could be officially launched, the PSI2-program of the COMUE Université Paris-Saclay acted as a predecessor. PSI2 operated two series of programs simultaneously; one devoted to Astrophysics and Cosmology and a second series of programs devoted to Physics and its interfaces. The following thematic programs were selected by the PSI2-Scientific Council for 2017, 2018 and 2019:
Program Managers: Stephanie Hessing and Karolina Kolodziej