This book constitutes the refereed proceedings of the 26th International Conference on Principles and Practice of Multi-Agent Systems, PRIMA 2025, held in Modena, Italy, during December 16-19, 2025.
The 25 full papers and 20 short papers included in this book were carefully reviewed and selected from 126 submissions.The conference also included three invited talks on cutting-edge topics in Artificial Intelligence and Multi-Agent Systems, presented by: Matteo Baldoni, University of Turin (Italy), Takayuki Ito, Kyoto University (Japan), and Alessio Lomuscio, Imperial College London (United Kingdom).