A quantitative review of 55 studies supports the conclusion that job attitudes are robust predictors of organizational citizenship behavior (OCB). The relationship between job satisfaction and OCB is stronger than that between satisfaction and in-role performance, at least among nonmanagerial and nonprofessional groups. Other attitudinal measures (perceived fairness, organizational commitment, leader supportiveness) correlate with OCB at roughly the same level as satisfaction. Dispositional measures do not correlate nearly as well with OCB (with the exception of conscientiousness). The most notable moderator of these correlations appears to be the use of self- versus other-rating of OCB; self-ratings are associated with higher correlations, suggesting spurious inflation due to common method variance, and much greater variance in correlation. Differences in subject groups and work settings do not account for much variance in the relationships. Implications are noted for theory, practice, and strategies for future research on OCB.