This study evaluated the psychometric properties of the Body Knowledge Questionnaire (BKQ), an instrument that measures weight management integration: an individual’s attitudes, preferences, and behaviors associated with weight self-management. The BKQ was revised following a pilot study demonstrating its validity and reliability, and new items were added based on data gathered through four focus groups of obese and normal-weight survey completers. Additional items were derived from the extant literature on weight management and integration. A panel of 30 health professionals who work in the area of weight management, bariatrics, and nutrition science reviewed the revised BKQ for content validity. Two hundred sixty-seven participants, recruited through Walden University’s online participant pool, completed the revised 66-item BKQ through SurveyMonkey. Exploratory factor analysis yielded a five-factor solution (Emotional Eating, Health-Conscious Lifestyle, Conscientious Eating Habits, Food Centricity, and Psychosomatic Awareness), with factor loadings >.40. Discriminant function analysis determined that the BKQ full scale and subscales could predict the classification of participants into normal-weight and obese groups for the total sample with 71% and 79% accuracy, respectively. Test–retest reliability was .86, and internal consistency of the overall BKQ was .92. The BKQ instrument has potential for use in individual or group weight management programs and program evaluation; for use in weight management practice areas such as dietetics, diabetes education, nursing, and psychology; or in the development of new weight management interventions.