This study was an investigation of intergenerational relationships related to the individuation process as reported by Mexican (N = 2,388) and European American (N = 2,907) adolescents. The primary aim was to examine the construct within theories of adolescent development that emotional separation in parent-adolescent relationships is an inherent aspect of the developmental process that occurs across the two ethnic groups. The authors conducted confirmatory factor analyses on a subscale INFUS of an instrument developed to measure family process, the Personal Authority in the Family System Questionnaire (PAFS-Q) developed by Bray, Williamson, and Malone. In sum, findings indicate: (1) the need for better measurement testing; (2) the need to revisit the concept of autonomy from the family as a universal task during adolescent development; and (3) caution in the clinical use of concepts such as fusion and independence when delivering mental health services to Mexican adolescents and their families.