The symposium on Properties Related to Fracture Toughness was presented at the Seventy-eighth Annual Meeting of the American Society for Testing and Materials held in Montreal, Canada, 22—27 June 1975. Committee E24 on Fracture Testing of Metals sponsored the symposium. W. R. Warke, Illinois Institute of Technology, Volker Weiss, Syracuse University, and George Hahn, Battelle Memorial Institute, presided as symposium cochairmen.