This volume contains the proceedings of the 5th International Conference on Estuarine and Coastal Modeling held in Old Town Alexandria, Virginia, October 22-24, 1997. The conference included oral and poster sessions describing recent model developments, applications, and interpretations and visualization of results. Special sessions were held on the state of the art in nowcasting and forecasting of the currents for the sailing events associated with the 1996 Olympic Games. The poster sessions featured the presentation of a wide variety of model results for hydrodynamic and water quality simulations. Each paper in the publication was presented orally or in a poster session at the conference and peer reviewed prior to acceptance. The authors represent a well balanced mix of professionals from private industry, government, and academic institutions from the US and abroad.