Earthquake Ground Motion is a compilation of ten chapters covering tectonics, seismicity, site effects, tsunamis, infrastructure, and instrumentation. It presents state-of-the-art techniques for retrieving rupture models, seismogenic structures, and validation of focal mechanisms. It also presents macroseismic archiving tools for historical and instrumental earthquakes and the fundamentals of seismic tomography. The book describes the site response analysis in 2D and 3D, considering topographic and soil structure interactions, its incorporation in a seismic hazard analysis, and the impact of earthquakes on the cost of reconstruction. The final sections are devoted to the genesis of earthquakes tsunamis, non-seismic tsunamis, and the new role of gyroscopes in rotational seismology.