AbstractEmotion regulation is widely studied in many areas of psychology and the number of publications on emotion regulation has increased exponentially over the past few decades. Additionally, interest in the relationships between emotion dysregulation processes and psychopathology has drastically increased in recent years. The Emotion Regulation Questionnaire (ERQ) was developed to measure two specific constructs related to emotion control: reappraisal and suppression (Gross & John, 2003). In its initial validation study and subsequent analyses, the instrument was shown to possess sound psychometric properties, but, to date, inquiry regarding the measure's characteristics has been limited. Factor analytic examinations of commonly used instruments are recommended to validate the properties of a given measure and increase researchers understanding of the measured constructs. The current study examined the psychometric properties of the ERQ in a sample of 1,188 undergraduates through confirmatory factor analysis. Additionally, tests of measurement invariance were employed in order to examine potential structural differences based on gender and ethnicity. The current study supported the original structure of the measure with all demographic groups and exceptional fit was demonstrated. Additional normative data for gender and ethnic groups are included. Results support the use of the instrument in future research. © 2011 Wiley Periodicals, Inc. J Clin Psychol: In Session 67:1–11, 2011.