Although efforts to improve freight transportation efficiency and reliability have been successful, the U.S. transportation system is now facing challenges that, unless addressed, may jeopardize its reliability. Allowing transportation system reliability to erode would add additional pressure to U.S. companies operating in an increasingly competitive international market and place more burdens on communities seeking to sustain their economic base and quality of life. Improved logistics has thus far been able to address the corrosive effects of the loss of system reliability. Unfortunately, the ability of logistics to provide additional offsetting savings appears to be nearing its limit, as are the savings attributable to deregulation. Unless these challenges are addressed, more discretionary income will be devoted to moving materials and products, businesses will be constrained in their adoption of innovative strategies to maintain global competitiveness, quality of life-as measured by congestion-will suffer, and safety and security could be jeopardized.