AIMS: In this study we investigated the effects of the physical work environment on two physiological measures of the stress response. METHODS AND RESULTS: Circadian variations in vagally mediated heart rate variability (HRV) and the morning rise in cortisol were evaluated in 60 participants working in a government building either in a traditional (individual offices and old cubicles; n=40) or a modern workspace (individualized cubicles with improved views and lighting; n=20). Results revealed significant linear (B=-1.03; confidence interval: -1.05 to -1.01, P<0.05) and quadratic (B=1.001; confidence interval: 1.0004-1.002, P<0.05) trends by office type interactions for indices of vagally mediated HRV. Individuals in the old office space had flatter slopes and thus less circadian variation including less HRV at night, and a larger rise in cortisol upon awakening compared with those in the new office space. CONCLUSION: These results indicate that physical features of the work environment may affect two aspects of the physiological stress response: circadian variations in HRV and the morning rise in cortisol. These findings have important social, economic, and public health implications for work environment risk factors on health.