Gratitude and anger represent 2 fundamental moral emotions in response to help or harm. Research suggests that individuals perceive organizations to have humanlike qualities and thus hold them responsible for helpful or harmful treatment. Given this line of reasoning, we hypothesized that workers direct gratitude toward their organizations in response to supportive treatment and anger toward their organizations in response to unsupportive treatment. Gratitude and anger, in turn, were expected to influence daily extrarole behavior. After developing short measures of organization-directed anger and gratitude in 2 pilot studies, we tested these hypotheses in a daily diary study of 54 workers providing 421 daily reports. Results indicate that perceived organizational support was related to chronic gratitude and anger, which is stable from day to day, and chronic gratitude was in turn related to chronic differences in organizational citizenship behavior. Episodic anger and gratitude, which vary daily, were related to daily supervisor interactional justice and helping behavior, respectively, and in turn predicted daily episodic variance in organizational citizenship and counterproductive work behavior. These findings suggest that the moral emotions of gratitude and anger toward the organization are indicators of employee affective well-being and play a mediating role in the effects of organizational and supervisor supportiveness on employee performance.