Effects of three office color schemes (red, blue-green, and white) were examined for 90 workers＇ mood and productivity, taking into account individual differences in environmental sensitivity (high screeners vs. low screeners). Matched on relevant variables, subjects were assigned to one of three offices. Workers performed office tasks for 4 consecutive workdays. Workers in the red office reported more dysphoria than workers in the blue-green office. Low screeners reported more dysphoria in the red and white offices than high screeners. High screeners pei-Sor med better on office tasks in the red office and poorer in the blue-gr-een office than low screeners. The results for performance al-e discussed as an extension of the Yerkes-Dodson principle, while the results for mood tended to support previous findings.