This book describes the practical aspects necessary to design, manage, monitor, and assess these hydraulic structures. The approaches, used to develop tools and methods for assessing performance and safety of dams largely applied for French cases, has been discussed for aggregating heterogeneous information and expert knowledge. Field measurements have been applied to the performance and the safety assessment for two real-life examples of old dams: Zermanice Concrete Dam and Sance Rockfill Dam in the Czech Republic. The finite element models (FEM), to simulate the crucial loading and monitoring stages of these dams, indicate heave, tilting, uneven displacements, and large settlements. Dam safety and risk management have been performed through the design of spillways, energy dissipators, dams' aseismic air-cushion control, simulation of aseismic mechanisms, control optimisation using shaking table tests, and the opportunity to use optic fibre crack sensing to prevent seismic damage.