The following proceedings contains most of the contributions given at Orbis Scientiae 1981. As has become customary during the past few years, the organizers and moderators have attempted to strike a balance between reviews of the status of experimental and theoretical developments during the preceding year. We are very pleased that experimentalists representing the critical developments in new accelerator plans, neutrino oscillations, proton decay, and decay schemes of the upsilon, have seen fit to enlighten at first hand their theoretical colleagues. We believe that this interaction can be...