This book includes extended and revised selected papers from the 12th International Conference on Smart Cities and Green ICT Systems, SMARTGREENS 2023, and 9th International Conference on Vehicle Technology and Intelligent Transport Systems, VEHITS 2023, held in Prague, Czech Republic, in April 2023. The 10 full papers presented in this book were carefully reviewed and selected from 80 submissions. These papers contribute to our understanding of relevant trends currently underway in research on Smart Cities and Green ICT Systems, & Vehicle Technology and Intelligent Transport Systems.