Seismic assessment and earthquake-resistant design are essential applications of earthquake engineering for achieving seismic safety for buildings, bridges, infrastructure, and many other components of the built environment. The Endurance Time Method (ETM) is used for seismic analysis of simple and complex structural systems and civil engineering infrastructure as well as producing optimal and cost-effective structural and detail designs. ETM is a relatively new approach to seismic assessment and design of structures. It has developed into a versatile tool in the field, and its practical applications are expected to increase greatly in the near future.