  We discuss pair production of stops, sbottoms, staus and tau--sneutrinos at a
$\mu^+ \mu^-$ collider. We present the formulae for the production cross
sections and perform a detailed numerical analysis within the Minimal
Supersymmetric Standard Model. In particular, we consider sfermion production
near $\sqrt{s} = m_{H^0}$ and $\sqrt{s} = m_{A^0}$.
