This project supports cooperation between Dr. Richard H. Pratt of the University of Pittsburgh and Dr. P.P. Kane of the Indian Institute of Technology, Bombay, India. The main research area will be the study of elastic scattering (Rayleigh scattering) and inelastic scattering (bound-electron Compton scattering) of hard x-rays and soft gamma rays by atoms. The focus will be on the atomic physics which appears to largely determine photon-atom scattering. The proposed studies will also provide more accurate data needed by workers in medical diagnostics, applied radiation physics and reactor safety. Objectives include the study of near-threshold effects in elastic scattering, and improved understanding of Compton scattering from tightly-bound inner-shell electrons of high-Z atoms. Scope: The work involves joint experimental and theoretical research between highly-complementary ongoing research programs in photon-atom scattering. The U.S. and Indian scientists have successfully collaborated in research in this area in the past. The research has both basic research interests as well as potential applications that are beneficial to scientists and radiation professionals in the two countries. Training of students is an integral part of the project. The project is being supported under two grants: INT 9019385 to the University of Pittsburgh; INT 9102053 to the Indian Institute of Technology, Bombay