This book constitutes the refereed proceedings of the 23rd International Conference on Information Technologies and Mathematical Modelling. Queueing Theory and Related Fields, ITMM 2024, held in Karshi, Uzbekistan, during October 20&26, 2024. The 26 full papers included in this book were carefully reviewed and selected from 136 submissions. The papers are devoted to new results in queueing theory and its applications, and also related areas of probabilistic analysis. Its target audience includes specialists in probabilistic theory, random processes, and mathematical modeling as well as engineers engaged in logical and technical design and operational management of data processing systems, communication, and computer networks.