  We analyze the partial decay widths of sfermions decaying into charginos and
neutralinos $\Gamma(\tilde{f} -> f'\chi)$ at the one-loop level, including the
electroweak and strong corrections. We present the renormalization framework,
and discuss the value of the corrections. Since these corrections show
non-decoupling effects, we analyze the radiative effects induced by a heavy
squark sector into the lepton-slepton-chargino/neutralino couplings. We
conclude that some knowledge of the heavy sector is needed in order to provide
a sufficiently precise prediction for slepton observables at an $e^+e^-$ Linear
Collider.
