The relation between overly positive self-evaluations and psychological adjustment was examined. Three studies, two based on longitudinal data and another on laboratory data, contrasted self-descriptions of personality with observer ratings (trained examiners or friends) to index self-enhancement. In the longitudinal studies, self-enhancement was associated with poor social skills and psychological maladjustment 5 years before and 5 years after the assessment of self-enhancement. In the laboratory study, individuals who exhibited a tendency to self-enhance displayed behaviors, independently judged, that seemed detrimental to positive social interaction. These results indicate there are negative short-term and long-term consequences for individuals who self-enhance and, contrary to some prior formulations, imply that accurate appraisals of self and of the social environment may be essential elements of mental health.