Rare Supersymmetric Top Quark Decays

{Two supersymmetric decays of the top quark, $\text{thb}$ and $\text{tstopneu}$, are discussed within the framework of the Minimal Supersymmetric Standard Model with radiatively induced breaking of $SU(2)\times U(1)$. The present possibility of detecting these decays, given the available bounds on supersymmetric parameters, is compared with the situation a Next $e^{+}{e}^{-}$ Linear Collider would face if supersymmetric particles were still undiscovered after LEP~II. The indirect implications for $\text{thb}$ and $\text{tstopneu}$ of a possible detection of the bottom quark decay $\text{bsgamma}$ at the Standard Model level are taken into account. } % Invited talk presented to the {\it Workshop on Physics and Experiments with Linear $e^{+}{e}^{-}$ Colliders}, Waikoloa, Hawaii, April 1993