In supersymmetric SO(10) with large tan beta and Yukawa coupling unification lambda(t) = lambda(b) = lambda(tau), we compute the rates for lepton flavour violating processes. Experiments in progress or foreseen for mu --> e gamma, mu --> e conversion (and the dipole moment of the electron) are shown to provide very significant tests of the theory for all slepton masses up to about 1 TeV.
