PROTON AND ANTIPROTON CROSS-SECTIONS AT HIGH-ENERGIES

Measurements of the total cross section and of diffractive processes, which have been performed in the last decade at the high-energy hadron colliders, are presented and compared with earlier results at lower e nergy. The general properties of the scattering amplitude, as derived from fundamental principles, are discussed, together with the current models and with the recent theoretical developments based on QCD.