  We analytically compute the dominant contributions to the \beta-functions for
the top-Yukawa coupling, the strong coupling and the Higgs self-coupling as
well as the anomalous dimensions of the scalar, gluon and quark fields in the
unbroken phase of the Standard Model at three-loop level. These are mainly the
QCD and top-Yukawa corrections. The contributions from the Higgs
self-interaction which are negligible for the running of the top-Yukawa and the
strong coupling but important for the running of the Higgs self-coupling are
also evaluated.
