The objective of the present study was to evaluate the psychometric properties of a short DSM-IV-based assessment instrument designed to be used specifically in WLT settings, the Eating Disorders in Obesity (EDO) questionnaire. The validity and reliability of the EDO was measured as concordance with the EDE, and test-retest agreement of the EDO, respectively. Validity as well as reliability was found to be good for both eating disorders diagnoses and binge eating as a distinct symptom. Results suggest that the EDO is a short, easily administered instrument with good psychometric properties.