  This PhD thesis is concerned with one-loop virtual electroweak corrections to
arbitrary processes in the high-energy limit. Complete results are presented
for the leading and subleading logarithms of large ratios of energy scales to
mass scales. These results include the logarithmic dependence on the photon and
weak-boson masses, on the light-fermion masses, as well as on the Higgs- and
top-masses in the heavy-Higgs and heavy-top limit.
  All sources of electroweak logarithmic corrections are taken into account,
including the exchange of soft and/or collinear electroweak gauge bosons as
well as the renormalization-group running of the gauge, scalar and Yukawa
couplings.
  The logarithmic corrections are derived in a process-independent way,
resulting in simple analytic formulas that apply to arbitrary electroweak
processes that are not mass-suppressed in the high-energy limit. We also
present analytical and numerical applications for the processes: e^+e^- \to
f\bar{f}, e^+ e^- \to W^+W^-, ZZ, Z\gamma, \gamma\gamma and \bar{d}u \to W^+Z,
W^+\gamma.
