This book constitutes the refereed proceedings of the 9th International Conference on Intelligent Transport Systems, INTSYS 2025, held in Marietta, GA, USA, on December 10, 2025.The 10 full papers presented in this book were carefully reviewed and selected from 24 submissions.The papers are organized in the following topical sections: Electric Vehicles - Charging, Batteries, and Structural Safety; Vehicular Networking, V2X Communications, andCooperative Control; Security, Forensics, and Trust in Connected Mobility Systems; AI, Multimodal Learning, and Intelligent Mobility Applications and Posters & and Demos