This reference describes the analytics of monitoring and predicting dynamic security and emergency control through the illustration of theory and applications of energy functions defined on structure preserving models. The author primarily describes different facets of dynamic analysis of large bulk power systems such as system stability evaluation, dynamic security assessment, and adaptive protection, among others. To be used as a guide for software development of the dynamic security assessment of power systems, this book supports illustration of SPEFs by examples and case studies, including descriptions of applications in real time monitoring, adaptive protection, and emergency control.