  QCD one-loop corrections to the semileptonic process $e^+ e^- \to \mu^- \bar
\nu_\mu u \bar d$ are computed. We compare the exact calculation with a
``naive'' approach to strong radiative corrections which has been widely used
in the literature and discuss the phenomenological relevance of QCD
contributions for LEP2 and NLC physics.

High Energy Physics - Phenomenology