Erio Tosatti, deputy-head of the ICTP Condensed Matter Section and professor of physics at the International School for Advanced Studies (SISSA), gave a plenary lecture at the 85th National Meeting of the Societa Italiana di Fisica (SIF), held in Pavia from 20-24 September. He spoke about phenomena regarding solid, liquid and phase transitions under extreme pressures and temperatures, a topic that has been a major focus of ICTP/SISSA joint research efforts.