This paper investigates intermodal rail terminal operations and describes the development of a computerized decision support system to load containers on double-stack trains efficiently. The support system, referred to as the Double Stack Planner (DSP), simulates many tasks performed by rail personnel who manually assign containers to rail car locations. DSP's rule base may be modified to load trains according to a variety of loading strategies, however, all maintain platform and truck load restrictions. Comparisons of these loading strategies illustrate the sensitivity of different criteria to the load quality of a train.