Lepton-Flavor Violation in the Supersymmetric Standard Model with Seesaw-Induced Neutrino Masses

We examine the lepton-flavor violation caused by a Yukawa coupling matrix $y_{\nu ,ij}$ for right-handed neutrinos in the supersymmetric standard model. We stress that decay rates for $\tau \to \mu \gamma$ and $\mu\rightarrow e\gamma$ may reach the range to be accessible to near future experiments if left-right mixing terms in the slepton mass matrix are substantially large.