  We discuss radiative corrections to the Casimir effect from an effective
field theory point of view. It is an improvement and more complete version of a
previous discussion by Kong and Ravndal. By writing down the most general
effective Lagrangian respecting the symmetries and the boundary conditions, we
are able to reproduce earlier results of Bordag, Robaschik and Wieczorek
calculated in full QED. They obtained the correction E_0^(1) =
\pi^2\alpha/2560mL^4 to the Casimir energy. We find that this leading
correction is due to surface terms in the effective theory, which we attribute
to having dominant fluctuations localized on the plates.
