  We discuss a recent analysis of a dominant two-loop electroweak correction,
of O(G_F M_t^2), to the partial width of the decay of an intermediate-mass
Higgs boson into a pair of photons. The asymptotic-expansion technique was used
in order to extract the leading dependence on the top-quark mass plus four
expansion terms that describe the dependence on the W- and Higgs-boson masses.
This correction reduces the Born result by approximately 2.5%. As a by-product
of this analysis, also the O(G_F M_t^2) correction to the partial width of the
Higgs-boson decay to two gluon jets was recovered.
