  We analyze the associated production at future high--energy $e^+e^-$
colliders, of first generation sleptons with neutralinos and charginos in the
modes $e^+ e^-$ and $e \gamma$, in the framework of the Minimal Supersymmetric
extension of the Standard Model. We show that the production rates, in
particular for associated production of right--handed selectrons and the
lightest neutralino which in general is the first accessible kinematically, can
be much larger than the corresponding ones for second and third generation
scalar leptons and for scalar quarks. With the high--luminosities expected at
these colliders, the detection of first generation sleptons with masses
significantly above the kinematical two--body threshold, $\sqrt{s}=
2m_{\tilde{l}}$, is thus possible in favourable regions of the parameter space.
