We summarize our recent results on the resummation of hard-scattering coefficient functions and on-shell form factors in massless perturbative QCD. The threshold resummation has been extended to the fourth logarithmic order for deep-inelastic scattering, Drell-Yan lepton pair production and Higgs production via gluon-gluon fusion. The leading six infrared pole terms have been derived to all orders in the strong coupling constant for the photon-quark-quark and the (heavy-top) Higgs-gluon-gluon form factors. These results have many implications, most notably they lead to a new best estimate for the Higgs production cross section at the LHC.

12 pages, LaTeX, 2 eps-figures. Uses modification appbav.cls (included) of the appolb.cls style. Presented by S.M. and A.V. at the conferences `Matter to the Deepest', Ustron (Poland), September '05, and RADCOR 2005, Shonan Village (Japan), October '05. To appear, in the latter case in shortened form, in the proceedings