This set of 19 volumes gathers the proceedings of the 12th International Conference on Applied Human Factors and Ergonomics (AHFE), held virtually on July 25-29, 2021. By highlighting the latest theories, models, as well as technologies and applications, and by combining findings from a range of disciplines including engineering, design, healthcare, computer science, management and social sciences, this set provides researchers and practitioners with extensive, timely information on current human factors research and developments. It is also intended to stimulate innovative ideas, and fostering discussions and interdisciplinary collaborations.