  The main challenge in computing inclusive cross sections and decay spectra in
QCD is posed by kinematic thresholds. The threshold region is characterized by
stringent phase-space constraints that are reflected in large perturbative
corrections due to soft and collinear radiation as well as large
non-perturbative effects. Major progress in addressing this problem was made in
recent years by Dressed Gluon Exponentiation (DGE), a formalism that combines
Sudakov and renormalon resummation in moment space. DGE has proven effective in
extending the range of applicability of perturbation theory well into the
threshold region and in identifying the relevant non-perturbative corrections.
Here we review the method from a general perspective using examples from deep
inelastic structure functions, event-shape distributions, heavy-quark
fragmentation and inclusive decay spectra. A special discussion is devoted to
the applications of DGE to radiative and semileptonic B decays that have proven
valuable for the interpretation of data from the B factories.
