This book constitutes the refereed proceedings of the 25th International Conference on Product-Focused Software Process Improvement, PROFES 2024, held in Tartu, Estonia, during December 2-4, 2024. The 18 full papers, 12 short papers, 9 Industry papers, 2 Workshop papers, 2 Doctoral symposium papers, and one Keynote paper presented in this volume were carefully reviewed and selected from 85 submissions. The main theme of PROFES 2024 was professional software process improvement (SPI) motivated by product, process, and service quality needs. The technical program of PROFES 2024 was selected by a committee of leading experts in software process improvement, software process modeling, and empirical software engineering.