This chapter presents both deterministic and probabilistic approaches to Seismic Hazard Analysis (SHA) which is Step 3 of the proposed hybrid approach in the context of dam engineering. The fundamentals of Probabilistic Seismic Hazard Analysis (PSHA) are introduced, including source modeling, empirical ground motion models (GMMs), and hazard curves. The chapter also discusses site-specific studies, deaggregation techniques, and ground motion selection and scaling.