The Sex-Role Egalitarianism Scale (SRES) was developed to measure attitudes toward the equality of women and men across content domains representing marital, parental, employment, social–interpersonal–heterosexual, and educational roles. The instrument exists in four versions: two alternate 95-item full forms and two alternate 25-item abbreviated forms. Reliability indices derived from a classical test-theory approach, multifaceted generalizability procedures, and an item-response theory-based analysis all support consistency or precision of measurement. Evidence for convergent, discriminant, and nomological validity is presented, along with a series of recommendations for future psychometric and substantive research using the scale.