One must consider both trait and state affect to predict individual differences in emotional processing. The present results document a novel trait-state interaction that is consistent with proposals concerning the epistemic functions of affect (A. R. Damasio, 1994). Four studies tested the effects of extraversion and mood on motivation-relevant processing. Study 1 measured naturally occurring mood, whereas Studies 2-4 manipulated mood. Extraverts were faster to link events to their personal motivations when in a positive mood state, whereas introverts were faster to do so in a neutral or negative mood state. Further findings indicate that this interaction affects attitude accessibility rather than event elaboration. Overall, the authors suggest that there are pragmatic benefits to trait-consistent moods, particularly for processing motivation-relevant stimuli.