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ABSTRACT A 1987 bridge failure in upstate New York, which cost ten lives, resulted in establishing a national (U.S.) program that requires each state to evaluate all their bridges over water for vulnerability offailure from erosion of their foundations (scour). This evaluation is to be carried out by an interdisciplinary team consisting of hydraulic, structural, and geotechnical engineers. This evaluation is in addition to the National Bridge Inspection Program that requires the states to inspect all bridges every two years to determine their structural integrity. To aid the states in the evaluation program two publications were issued, HEC-18 entitled, “Evaluating Scour at Bridges” and HEC-20, “Stream Stability at Highway Structures.” These publications give guidelines for doing the evaluations; give equations and methods for computing scour; suggest a design philosophy that bridges should be designed using the flow for a 100–year return period flood and to withstand the effects of scour from a superflood (a flood exceeding the 100–year flood); give instructions for inspection of bridges for scour vulnerability; and describe countermeasures to protect bridges from scour This article provides an overview of the magnitude of the bridge scour problem in the U.S., procedures and results from the ongoing National evaluation program, and current practices and equations for analyzing bridges for scour A number of refinements to the HEC-18 procedures for analyzing scour are suggested. Sources of technology transfer are referenced and highlighted, including a training course on bridge scour and stream stability; instrumentation being developed in the U.S. to monitor scour at bridges is described.