The following thesis is dealing with the fundamental topic of dam safety and methods of risk assessment for embankment dams. At the beginning of the work, an overview of possible failure mechanisms of embankment dams is presented. The general term of dam safety, as well as the Austrian safety concept for dams is discussed against the backdrop of international normative principals. During the further procedure, the theoretical basics of the concept of dam risk assessment are presented. Starting with the estimation of the probability of failure of spillways and bottom outlets, approaches for calculating the probability of failure due to overtopping are discussed. Furthermore, concepts for estimating the probability of internal erosion are presented. The theoretical part of this thesis will conclude with remarks about the determination of failure hydrographs, the basics of flood wave analysis and the study of consequences in case of a dam failure. The application of the presented framework of a quantitative risk assessment will be demonstrated on the basis of two case studies. Furthermore, the differences between permanently and non-permanently impounded reservoirs will be presented and discussed. A special focus is set on the failure mechanism of slope failure and failure due to internal erosion. For estimating the consequences, a substantial flood wave analysis is conducted, which builds the basis for the concluding estimation of the potential loss of life. Finally, the gained results will be evaluated by reference to international standards of dam risk assessment.