  We propose a general formula for calculating the entanglement entropy in
theories dual to higher derivative gravity where the Lagrangian is a
contraction of Riemann tensors. Our formula consists of Wald's formula for the
black hole entropy, as well as corrections involving the extrinsic curvature.
We derive these corrections by noting that they arise from naively higher order
contributions to the action which are enhanced due to would-be logarithmic
divergences. Our formula reproduces the Jacobson-Myers entropy in the context
of Lovelock gravity, and agrees with existing results for general
four-derivative gravity.
  We emphasize that the formula should be evaluated on a particular bulk
surface whose location can in principle be determined by solving the equations
of motion with conical boundary conditions. This may be difficult in practice,
and an alternative method is desirable. A natural prescription is simply
minimizing our formula, analogous to the Ryu-Takayanagi prescription for
Einstein gravity. We show that this is correct in several examples including
Lovelock and general four-derivative gravity.
