  The Standard-Model Extension (SME) is an action-based expansion describing
general Lorentz violation for known matter and fields, including gravity. In
this talk, I will discuss the Lorentz-violating gravity couplings in the SME.
Toy models that match the SME expansion, including vector and two-tensor
models, are reviewed. Finally I discuss the status of experiments and
observations probing gravity coefficients for Lorentz violation.
