This book is a collection of original peer-reviewed contributions from the 2023 International Conference on SmartRail, Traffic, and Transportation Engineering, jointly organized by Beijing Jiaotong University, China Electrotechnical Society, Chinese Institute of Electronics and Central South University. It was held on July 28-30, 2023 in Changsha, China. Topics covered includes SmartRail systems, autonomous vehicles, energy efficiency, sustainable transportation, big data in transportation, and machine learning. Speakers discussed innovative technologies and strategies to improve the efficiency, reliability, and safety of rail networks, while exploring the opportunities and challenges of integrating autonomous vehicles into existing transportation networks. It provides valuable insights into the latest developments and trends in transportation engineering and technology, with a focus on electrification and sustainable transportation. It serves as a valuable resource for professionals, researchers, and students working in the field.