This proceedings contains the talks delivered at the plenary and parallel sessions. Topics covered include e⁺e⁻ Physics at Z0, String Theory and Theory of Extended Objects, High Energy pp Physics, Non-Accelerator Particle Physics, Conformal Field Theory, e⁺e⁻ Physics below Z⁰, Structure Functions and Deep Inelastic Scattering, Neutrino Physics, Recent Developments in 2-Dimensional Gravity, Lattice Gauge Theory and Computer Simulations, CP Violation , Accelerator Physics, Cosmology and Particle Physics, Interface Between Particle and Condensed Matter Physics, Detector R&D, and Astroparticle Physics.

The proceedings of the 4th Italy-Japan Symposium on Heavy Ion Physics cover the following fields of nuclear physics: heavy ion nuclear reactions; nuclei under extreme conditions; nuclear astrophysics; photon detectors and physics; technology of RI beams and experimental instrumentation; application of RI beams.