The Standard Model describes elementary particle interactions in terms of gauge theories: Quantumchromodynamics (QCD) for the strong interactions and the Glashow-Weinberg- Salam agreement with experiment. However, it does not naturally explain the particle mass spectrum, the breaking of electroweak gauge symmetry, or the different strengths of the QCD and GWS couplings: these deficiencies strongly indicate the existence of a Higgs particle and possible new interactions at energies which will become available in the near future. Perturbation theory, a power series expansion, may be used to study QCD at high energies. However, the expansion parameter is not small and higher-order corrections are substantial. These corrections will be computed for various lepton and hadron reactions to obtain reliable predictions of cross section normalizations, and transverse momentum and other distributions. These predictions will allow for more precise tests of QCD; they will aid in studying non-perturbative effects due to strong quark-gluon forces in initial-state hadrons and in hadron jets; and they will facilitate unambiguous identification of signals of the electroweak and possible new interactions. Production of GWS gauge bosons and of the Higgs boson will be studied: signals will be compared with QCD backgrounds, and unusual signals which exhibit properties, such as parity-violation, that are not shared by the background will be identified. These results, to be obtained by a very highly-regarded and capable elementary particle theorist, will enable precision tests of the Standard Model to be made at accelerators presently in operation or under construction, and will aid in the design and execution of experiments searching for new particles and interactions at future super colliders.