In recent decades, time-dependent density functional theory has been developed for computing excited-state properties of large-scale systems to high accuracy in biomolecules and nanomaterials, especially for ab initio nonadiabatic molecular dynamic simulations. It is therefore regarded as a most unique efficient method to do accurate simulation for large complex systems. This book compiles and details cutting-edge research in quantum chemistry and chemical physics from interdisciplinary groups from Japan, China, South Korea, the United States, Hong Kong, and Taiwan. These groups are developing excited-state dynamics methods involving conical intersections and intersystem crossings for large complex systems. Edited by Chaoyuan Zhu, a prominent chemical physics researcher, this book will appeal to anyone involved in molecular dynamics and spectroscopy, photochemistry, biochemistry, and materials chemistry research.