The median age of bridges in the National Bridge Inventory is about 44 years. Many bridges built to design codes that are older and less demanding than current codes will be required to exceed their original design lives. Therefore, state highway agencies will need to expend more resources to prevent deterioration of their bridges, and the most efficient ways of assessing and maintaining the stock of bridges must be found. In addition, new bridges must be designed for durability, and key components must be accessible and capable of being maintained. This paper discusses various deterioration mechanisms, such as fatigue, impacts, scour, concrete deterioration, and corrosion, that can affect current highway bridges; issues concerning durability, maintainability, assessment, and monitoring of bridges; rehabilitation of bridges; and design of new bridges. The training of new engineers and the provision of expertise and allocation of resources by state highway agencies are also discussed. A holistic approach to transportation infrastructure maintenance is viewed as ensuring that all relevant expertise and experience are available to contribute to the design, construction, maintenance, and rehabilitation of new and existing bridges.