Introduction: Obesity and its related conditions such as diabetes and heart disease are unfortunate side effects of the medications used to treat veterans with severe mental illness. In combination, obesity and severe mental illness pose a huge public health problem. The FDA and the VA inspector general are concerned about the monitoring and safety of severely mentally ill patients taking antipsychotic medications. This research is designed to test a multi-modal approach to the problem of antipsychotic medication associated obesity over a 12-month period at 4 different VA settings. Though the MOVE program has been developed to combat obesity in the general VA population, there exists a large portion of patients with severe mental illness who cannot or will not access MOVE. This program is designed to fill the gap that usual care does not provide. This study will test this special intervention for severely mentally ill patients taking antipsychotic medications and comparing this intervention to usual care at 4 VA sites. Methods: 120 veterans from four different VA sites will be randomly assigned to either a 12 month multi-modal behavioral treatment program vs. usual care for the monitoring and treatment of medication associated obesity. The multi modal treatment approach, the Lifestyle Balance Program adopted from the federally funded Diabetes Prevention Program, is aimed at changing lifestyles and includes individual health coaching, and group classes weekly for the first 8 weeks, as well as a prescribed individualized plan for exercise and dietary changes that will result in weight loss. Additionally, counseling with caregivers on support of lifestyle changes will be provided and meal substitution will be implemented for veterans who have no control over food provided to them in institutional type settings (e.g. board and care homes). Following the initial 8 weeks, individual coaching and group booster classes will occur for the next 10 months on a monthly basis. This study will also test the ability of other VA sites to adopt a weight loss program for this particular population. Preliminary Results: This is a continuation of an ongoing program in which 120 veterans have already participated. Thus far, our preliminary results have been promising. We have observed twice the weight loss that we anticipated in the initial grant period over a year long weight loss program. We have seen improvements in certain symptoms of mental illness, as veterans appear to be more outgoing and less withdrawn. We also have seen a positive impact on veterans'well being and the quality of their lives. Additionally we have achieved with weight loss an improvement in risk factors for heart disease. This prolongs the lives of veterans with severe mental illness and translates into cost savings for veterans, their families, and society in general. This new study will determine if the success at our one site can be achieved at three additional sites.