State optimism was hypothesized to be significantly related to six organizationally relevant outcomes above and beyond the effect of trait optimism. Moreover, state optimism was hypothesized to have effects on these six outcomes beyond the effects of positive and negative affect. Conversely, trait optimism was expected to be unrelated to the six outcome variables when controlling for state optimism as well as when controlling for affect. These hypotheses were tested with two samples. First, 772 undergraduate students were assessed to determine the impact of state versus trait optimism on task performance in the form of course grade. From this sample, the 261 students working at least 20 hours per week were similarly assessed with regard to work related distress, burnout, affective commitment, and job satisfaction. Then, a field sample of 106 employees assessed distress, burnout, affective commitment, job satisfaction, and supervisor rated task and contextual job performance. Results indicate state optimism (but not trait optimism) is a potentially powerful indicator of important organizational outcomes, even after controlling for the effects of positive and negative affect. Implications of these findings and directions for future research are discussed. Copyright © 2009 John Wiley & Sons, Ltd.