Investigators of personality assessment are becoming aware that using positively and negatively worded items in questionnaires to prevent acquiescence may negatively impact construct validity. The Rosenberg Self-Esteem Scale (RSES) has demonstrated a bifactorial structure typically proposed to result from these method effects. Recent work suggests that these method effects may have substantive meaning. These studies examined the relation between method effects associated with positively and negatively worded items in the RSES and primary, broad personality constructs: approach and avoidance motivation and the "Big Five" (emotional stability, extraversion, intellect, agreeableness, and conscientiousness). A series of confirmatory factor analyses revealed that method effects are required in the measurement model of self-esteem and are related to important personality constructs.