The current paper demonstrates the application of displacement-based procedure in the seismic safety assessment of large concrete dams. Two dam structures—double-arch and gravity, are used as case studies and analysed through conventional force-based approaches, for various Seismic Levels. Nonlinear static analyses are used for assessment of structural capacity and nonlinear dynamic analyses—to obtain the maximum response for each Seismic Level. The dams’ safety is assessed totally based on displacements through displacement-based damage indicators in the form of Damage Indexes (DI) and Safety Factors (SF). The DI accounts for the accumulated inelastic deformations in the structure and are related to predefined Damage Levels (DL), while SF evaluates the structural safety margins in terms of seismic load intensity.