This session will cover the recent progress in understanding the structure and properties of glass under extreme conditions, such as high pressure, high stress, high temperature, high radiation, and highly reactive conditions. Many manufacturing processes, such as fiber drawing, laser writing, and irradiation aging, are concerned with these conditions. New knowledge of glass structure and properties under extreme conditions can help design new glasses for these applications, as well as in using such conditions to synthesize glasses with superior properties. Experimental studies, novel in situ analysis methods, and computational approaches are within the scope of this session.