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.