When individuals learn the outcome of an event or the correct answer to a question, they overestimate its prior predictability: that is, they tend to believe they “knew it all along.” Cognitive and motivational interpretations of hindsight bias are briefly reviewed and a study designed to test the motivational interpretation is reported. Specifically, it was hypothesized that individual differences in the strengths of two motives, a need for predictability and a self-presentation motive, should be positively related to individual differences in the magnitude of hindsight bias. Sixty-eight subjects completed a Dogmatism Scale and an Intolerance for Ambiguity Scale (the predictability motive) and the Marlowe-Crowne Social Desirability Scale (the self-presentation motive) before participating in a standard hindsight-bias paradigm. Measures of both motives, as well as a self-reported ego-involvement measure, were positively associated with the amount of hindsight bias exhibited. Implications of this result for interpretations of hindsight and other conceptually related phenomena are discussed.