  We analyze Doppler-effect experiments in terms of a general framework for
violations of Lorentz symmetry: the Standard-Model Extension. These experiments
are found to be sensitive to heretofore unprobed combinations of
Lorentz-violation coefficients associated with protons and electrons. New
bounds at the level of $10^{-11}$ and $10^{-8}$ for proton coefficients and
$10^{-2}$ for electron coefficients emerge from a recent experiment.
