Covering many different areas of sustainable water resource management, this volume is made up the the proceedings of the 28th International Association of Hydraulic Engineering and Research Congress held at Graz in 1999. It also contains papers presented at the Memorial Symposium for P. Forchheimer and A. Schoklitsch, and a CD-ROM. The themes covered include sub-surface hydraulics and engineering; hydraulic structures; information technology in water resources modelling and management; hydraulic and ecological interactions in a vulnerable environment; and fluvial systems - processes, functions and management.