Efficient freight mobility is the result of successfully balancing the demand for transportation capacity and service with the quantity supplied of those services and capacities. A growing number of communities and economic interests in the state of Washington recognized that efficient freight movement is directly associated with the health of their local and regional economies. As a result, state and local governments are being asked to improve freight mobility through operational improvements and new public infrastructure. Inter-modal truck-rail facilities, where goods are transferred from truck to rail or vice-versa, for shipment to domestic markets or through gateways to international markets, are offered, or sought, as a means of improving the freight movement in the area. Proposed public investment in such inter-modal facilities raises at least two questions: Will the facility succeed in the private market place by generating a sustaining return as a commercial investment? And, is any public investment justified based on the public benefits involved? It is the combination of internal efficiencies and external competition that will affect the economic viability of the inter-modal facility itself. A great deal of information and analysis is needed to identify these necessary attributes and those operating characteristics that “would or could” produce private economic viability and, if necessary, a requited rate of return on public investment. This paper reports on the development of an applied methodology for determining the potential economic viability of inter-modal truck-rail facilities in Washington State. The focus is on discerning the attributes, characteristics or market situations that are associated with successful projects, thereby suggesting a framework for economic feasibility analysis, from both the public and private view, of an inter-modal truck-rail facility. A conceptual approach and general model of investigation is first developed in the paper. A focused review of literature followed by a summary of actual and active inter-modal centers allows the development of a series of case studies/models, chosen as examples of facilities performing differing functions in the overall supply chain for exports and imports. These are then combined with a list of attributes that are useful, even critical, to viability, allowing prioritization of the attributes for each type of case study. This then leads to the conclusions and implications of the paper.