This book constitutes the proceedings of the 16th International Conference on Social, Cultural, and Behavioral Modeling, SBP-BRiMS 2023, which was held in Pittsburgh, PA, USA in September 2023. The 31 full papers presented in this volume were carefully reviewed and selected from 73 submissions. The papers were organized in topical sections as follows: Detecting malign influence; human behavior modeling; and social-cyber behavior modeling.