  I discuss the matching relations for the running renormalizable parameters
when the heavy particles (top quark, Higgs scalar, Z and W vector bosons) are
simultaneously decoupled from the Standard Model. The complete two-loop order
matching for the electromagnetic coupling and all light fermion masses are
obtained, augmenting existing results at 4-loop order in pure QCD and complete
two-loop order for the strong coupling. I also review the further sequential
decouplings of the lighter fermions (bottom quark, tau lepton, and charm quark)
from the low-energy effective theory.
