An International Symposium on Defects and Fracture was held in Tuczno, Poland, 13-17 October 1980 under the sponsorship of the Polish Academy of Sci ences and Institute of Fracture and Solid Mechanics, Lehigh University. Profes sor H. Zorski of the Academy and Professor G. C. Sih of Lehigh University were Co-Chairmen. The idea for the Symposium was initiated by the members of the Organizing Committee: G. C. Sih (Co-Chairman), H. Zorski (Co-Chairman), M. Matczynski (Secretary), D. R. Axelrad, R. Bullough, J. W. Provan and R. deWit. With the rapid development of high performance materials and...