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