Background <p>Does what a person desires to feel (affect valuation) predict their future affective reaction to salient life events? We tested this idea in the context of an exam, a key achievement-oriented event for college students.</p> Methods <p>One to two weeks prior to taking an exam (at baseline), 177 university students rated their ideal affect, depression and anxiety symptom severities, and provided affective forecasts for how they would react if they did or did not achieve their expected exam scores. On the day when students received their exam scores, they rated their actual emotional response to the exam outcomes.</p> Results <p>Higher levels of baseline ideal positive affect predicted greater positive affective responses to receiving satisfying exam scores. This prediction held even after controlling for affective forecasting, depression and anxiety levels, and the exam score itself. Higher levels of baseline ideal negative affect predicted greater negative affective reactions to receiving disappointing exam scores, but did not survive parallel statistical controls.</p> Conclusions <p>These findings suggest motivational functions for ideal affect, particularly for positive affective states.</p>