OBJECTIVES: The Chronic Care Model (CCM) is a framework for enhancing health care delivery for chronic illnesses through six elements: self-management support, delivery system design, community resources, organizational support, decision support, and clinical information systems.  The CCM was implemented at USAF Wilford Hall Medical Center from 2006 through 2008, but little is known about its long-term effectiveness. METHODS: We used the ARCHeS interface to the Archimedes model to forecast the effectiveness of the CCM compared to the current levels of care in the US (CLC) over 20 years for patients with type 2 diabetes.  We modeled the CCM intervention effects on health outcomes and disease progression of diabetes based on empirical biomarker change results from three-year military-based clinical data.  The primary analysis focused on the effectiveness in terms of diabetes related health outcomes, while a secondary analysis considered cost-effectiveness from a health care system perspective. RESULTS: Compared with CLC, the relative reductions in 20-year Kaplan-Meier incidence due to the CCM were 10.3%, 3.8%, 5.8%, 6.0%, 11.1% for myocardial infarction, proliferative diabetic retinopathy, blindness, foot ulcer, and foot amputation, respectively.  The CCM resulted in a 6.7% relative reduction in coronary heart disease death, and a 0.6% relative reduction in all-cause death.  The CCM had no compelling benefits for reducing the incidence of stroke or nephropathy. CONCLUSIONS: We found the CCM lowers the risk of morbidity and mortality from diabetes in a military population.  Our results using ARCHeS simulations are broadly consistent with previous Markov model studies but extend those results by providing a more detailed understanding of the specific health outcomes affected by the CCM, as well as the impact on comorbidities associated with diabetes.