The Symposium on Damage Tolerance in Aircraft Structures wasconducted in two sessions at the Seventy-third Annual Meeting ofthe American Society for Testing and Materials, held in Toronto,Ontario, Canada, 21-26 June 1970. The symposium was sponsored byASTM Committee E09 on Fatigue. M. S. Rosenfeld, of the Naval AirDevelopment Center, served as symposium chairman, with P. C. Paris,Del Research Corp., Hellertown, Pa., and R. J. Hebert, Canadair,Ltd., Montreal, Ontario, presiding as chairmen of the first andsecond sessions, respectively.