Debates about the utility of conscientiousness as a predictor of job performance have focused
primarily on mean effect size estimates, despite theoretical and empirical reasons to expect
variability across situations. The present study meta-analytically demonstrates that occupation-level situational strength is one important source of this variability. Consistent with
theory, predicted uncorrected conscientiousness–performance correlations ranged from
r¼.09 to .23 (overall performance) and r¼.06 to .18 (task performance), with stronger
correlations observed in weak occupations. These results highlight the need for continued
inquiry into the nature of situational strength, its impact on other predictor–outcome
relationships, and the implications of these issues vis-a`-vis theory and practice. Copyright
#2009 John Wiley & Sons, Ltd.