The 1989 Cargese Summer Institute on Particle Physics was organized by the Universite Pierre et Marie Curie, Paris (M. Levy and J.-L. Basdevant), CERN (M. Jacob), the Universite Catholique de Louvain (D. Speiser and J. Weyers) and the Katholieke Universiteit te Leuven (R. Gastmans), which, since 1975, have joined their efforts and worked in common. It was the twenty-sixth Summer Institute held at Cargese and the tenth organized by the two Institutes of Theoretical Physics at Leuven and Louvain-la-Neuve. The 1989 school centered on the following topics - new experimental results - strings, superstrings and conformal field theory - lattice approximations. Of the many new experimental results, we would like to mention especially those from SLAC presented by Professor G. Feldman. On the other hand, we had the tantalizing knowledge that LEP would begin to operate only right after the end of the school! For this we received ample replacement: Professor J. Steinberger summed up all major CP violation experiments done to date and commented upon them. The reader will find also various other most interesting contributions, for instance on high energy ion beams. Once more theoreticians and experimentalists (this time more than usual) came together to discuss high energy particle physics.