The authors discuss the use of psychobiological measures (i.e., biomarkers) for furthering understanding of the biological foundations supporting human occupational behavior. They explore the possible applications of psychobiological measures in research relevant to occupational therapy practice and occupational science, including the documentation of outcomes following occupational therapy intervention. Common psychobiological measures that are available and of particular interest to occupational scientists and therapists are described based on a review of research that has applied psychobiological measures. Psychobiological measures have rarely been reported in the occupational science and occupational therapy literature to date, although such measures are beginning to emerge as researchers expand their questions and methods related to occupational engagement. Psychobiological measures may provide promising insights into the effectiveness of interventions designed to improve self-regulation and more effectively manage stressors for enhancing occupational performance. These measures also may be used to increase understanding of how participation in desired occupations influences arousal levels, stress response, and overall states of well-being and productivity.