Aqueous film forming foam (AFFF) is a water based foam that was historically comprised of per- and polyfluoroalkyl substance (PFAS)-based surfactants. AFFF has been used by the military since the 1970s for fire suppression in ships, shore fixed systems, aircraft hangars and to extinguish liquid fuel fires in aircraft rescue and fire fighting (ARFF) vehicles. In FY20, Congress mandated that PFAS be eliminated from AFFF by FY25. In this technical session, presentations provided details on the performance of PFAS-free alternatives including research on recently-developed novel surfactants at the laboratory scale as well as commercially available products demonstrated against representative large scale fires. This session also included updates on revisions to MIL-PRF-24385 to enable implementation of PFAS-free foams, as well as highlights from the 2021 SERDP AFFF Challenge featuring innovative approaches to fuel fire extinguishment from around the country.