The RACIRI Summer School is a joint initiative by Russia, Sweden and Germany in the collaborative framework of the Röntgen-Angström-Cluster (RAC) and the Ioffe-Röntgen-Institute (IRI). The format of the RACIRI Summer School is driven by scientific frontier themes and challenges in the field of materials sciences with a strong connection to the superb analytical potential at current and future research infrastructures for photons, X-rays and neutrons in the Baltic Sea region (synchrotron-radiation and free-electron-laser facilities as well as research reactors and spallation sources). The RACIRI Summer School is held every year under a special focus theme. Its venue rotates annually among the three partnering countries.