This book constitutes the proceedings of the 41th International Conference on Computers and Their Applications, CATA 2025, which took place in Honolulu, HI, USA, during March 23–25, 2026.The 35 full papers included in this book were carefully reviewed and selected from 68 submissions. They were organized in topical sections as follows: AI for Smart Infrastructure and Environmental Systems; AI in Healthcare and Public Health; Cybersecurity and Secure Systems, AI for Finance, Social Media, and Business Analytics; NLP, Sentiment, and Educational Data Mining; Advanced Software and AI for Networked Systems; Privacy, Cryptography, and Secure Architectures; and Advanced AI Models and Learning Architectures.