This book contains the 55 papers presented at the seventh International Conference on Hydraulic Engineering Software, held in Italy in September, 1998. Hydraulic engineering is ideally suited to the application of numerical methods, which in turn lend themselves to computational analysis. The rapid advances in computational techniques and the increasing speed and storage capacity of the PC have greatly improved the ability to solve complex problems in the hydraulic engineering field. In addition, recent improvements in graphical user interfaces have resulted in software packages becoming easier to use. The sophisticated software now available enables hydraulic engineers to simulate and predict events with a high degree of accuracy and, hence, to provide robust and cost-effective designs. The HYDROSOFT series of international conferences continues to attract high-quality papers from the hydraulic engineering software field, particularly in the broad areas of groundwater flow, free surface flow and pressure flow. A number of contributions on stochastic methods related to hydrology and intelligent software are also presented.