Inelastic scattering is very strong in the oxides and large momentum space
anisotropies exist in models in which the effective interaction is strongly
peaked at (pi,pi) in the 2-dimensional Brillouin zone. This situation is f
avourable to d-wave superconductivity and may apply to the oxides. We calcu
late the normal state optical conductivity and describe the relationship of
the derived optical-scattering rates and effective masses to the underlyin
g self energies with emphasis on frequency dependence and on anisotropy. Co
mparison with experiments is made. It is found that anisotropy leads to an
energy dependence in the optical rate even when the scattering is elastic.