  Advantages of the e-e- option at linear colliders for the study of
supersymmetry are highlighted. The fermion number violating process $e^- e^-
\to \selectron^- \selectron^-$ provides unique opportunities for studies of
slepton masses and flavor mixings. In particular, slepton mass measurements at
the 100 MeV level through threshold scans of scalar pair production may be
possible. Such measurements are over an order of magnitude better than those
possible in e+e- mode, require far less integrated luminosity, and may lead to
precise, model-independent measurements of $\tan\beta$. Implications for
studying gauginos and the importance of accurate beam polarimetry are also
discussed.
