  A large variety of jet properties can be described perturbatively by evolving
the parton cascade down to small scales of order of a few 100 MeV. We discuss
two recent applications of this approach: 1. the soft limit of the particle
spectrum which is nearly energy independent as expected for the soft gluon
bremsstrahlung; further tests of this interpretation in $e^+e^-$ and DIS are
presented; 2. the steep decrease of the distribution of rapidity gaps in
$e^+e^-$ annihilation can be explained by the Sudakov formfactor for quark
jets.

High Energy Physics - Phenomenology