This book comprises the papers of the International Conference on Hydraulics of Dams and Rivers Structures, held in Tehran, 26-28 April 2004. The topics covered include air-water flows, intakes and outlets, hydrodynamic forces, energy dissipators, stepped spillways, scouring and sedimentation around structures, numerical approaches in river hydrodynamics, river response to hydraulic structures and hydroinformatic applications. This proceedings provides professionals and researchers with news of interdisciplinary research findings, considering future development of the sector in its many and various applications.