Neutrino tests of Lorentz and CPT invariance

At low energies, residual effects of Planck-scale physics may manifest as tiny violations of Lorentz and CPT invariance. We discuss the possibility of searching for Lorentz and CPT violation in current and future neutrino-oscillation experiments. We analyze neutrino propagation in the context of the general Lorentz- and CPT-violating Standard-Model Extension. Candidate signals are identified.