In the year 2000, 31% of women and 40% of men receiving outpatient care at Veteran Affairs (VA) medical facilities were overweight (BMI ≥25 and <30 kg/m2); 37.4% of women and 32.9% of men were obese (BMI ≥30 kg/m2). The purpose of the present study was to assess treatment effects of MOVE! Weight Management Program for Veterans by comparing the trajectory of change in weight postintervention (3, 6, and 12 months postenrollment) to a preintervention period (1, 3, and 5 years before enrollment). The sample consisted of 862 veterans participating in MOVE! at the Miami VA. All veterans participated in a 2-h Self-Management Support (SMS) session, which involved completion of a self-assessment questionnaire and a nutrition education group session. After completing SMS, veterans had the option of continuing with Supportive Group Sessions (SGS), which included 10-weekly group sessions led by a multidisciplinary team. Veterans served as their own controls in the analyses. Veterans gained 2 kg/year before enrolling in MOVE!. There were similar increases in weight across sex, racial/ethnic groups, and treatment condition. Weight for participants in SMS stabilized after enrollment whereas participants in SGS had an average weight loss of 1.6 kg/year. The preintervention slope for weight was significantly different from the postintervention slope, suggesting treatment effect. Findings from this study support the need for a lifestyle modification program such as MOVE! in primary care settings to assist overweight and obese patients in managing their weight.