Nucleon-deuteron scattering is cast into the form of an optical potential formalism. Two forms of an optical potential are given. The resulting integral equations for the optical potentials are approximated by the first two leading terms. Our numerical results demonstrate that even at intermediate energies these approximations are insufficient to cover all of the angular range. Rescattering terms of higher order in the nucleon-nucleon (NN) t matrix are needed. If one focuses on forward scattering, low-order approximations in the NN t matrix can be sufficient, depending on energy, and observable. {copyright} {ital 1997} {ital The American Physical Society}