Physio-adaptive systems define a class of information systems that refer to an innovative mode where system interaction is reached by monitoring, analyzing, and responding to hidden psy-chophysiological user activity in real-time. However, despite a strong interest of scholars and practitioners in physio-adaptive systems, there exists a lack of a structured and systematic form in which physio-adaptive systems research can be classified. Against this backdrop, this article showcases the current state-of-the-art of physio-adaptive systems research along three different stages, namely (1) collection of physiological data, (2) state determination, as well as (3) system adaptation. Analyzing 44 articles during the years 1994 - 2019, our main contribution resides in the synopsis of physio-adaptive systems literature along these stages. For instance, we illus-trate that there exist three categories for adaptive responses: state display (20% of the analyzed studies), assistance offering (18%), and challenge adaptation (61%). On the grounds of our review, we propose seven promising avenues, which will support scholars in their endeavors on how to pursue with future research in the field of physio-adaptive systems.