This book collects several articles from the 2nd workshop BestPSHANI 2018 organized by the IAEA as well as several new contributions. The issue covers topics ranging from the seismological aspects of earthquake source studies, ground motion and fault displacement modeling to the engineering application of simulated ground motion for the analysis of soil structure interaction, structural response and fragility curve analysis for the quantification of seismic vulnerability of structures and their seismic performance. Collectively, the seismological papers discuss several current issues of source characterization and ground motion prediction for SHA, highlighting the usefulness of physics-based models for future applications in practice. The engineering papers describe methodologies to develop integral models from source-to-structures that consider the developments of synthetic seismograms as input for structural response and fragility curves estimation for seismic vulnerability assessment. The book is a valuable resource for scientists, engineers, students and practitioners involved in all aspects of SHA, FDHA and vulnerability analysis of engineering structures for seismic risk.