  We consider $1/Q$ corrections to hard processes in QCD where Q is a large
mass scale, concentrating on shape variables in $e^{+}e^{-}$ annihilation.
While the evidence for such corrections can be and has been established by
means of the renormalon technique, theory can be confronted with experiment
only after clarifying the properties of the corresponding non-perturbative
contribution. We list predictions based on the universality of the $1/Q$ terms,
and compare them with the existing data. We also identify the scale of the
non-perturbative contributions in terms of jet masses.

High Energy Physics - Phenomenology