Since the terrorist attacks of September 11, 2001, 1,348,405 citizens have been deployed to combat in Operation Iraqi Freedom (OIF), Operation New Dawn in Iraq, and Operation Enduring Freedom in Afghanistan (OEF). During this same period 266,810 (20%) of these individuals have been diagnosed with a traumatic brain injury (TBI). The majority of these were Army soldiers, with 155,282 (58%) receiving the diagnosis. Mild TBI comprised 82% of the total, with the remainder being moderate to severe. Over this same period the Department of Defense (DoD) has invested $374.9 million to enhance access and quality of care services, including 57 TBI treatment centers in the combat theater and throughout the U.S. The Army's medical research division, the Medical Research and Material Command (MRMC), has invested an additional $700 million to TBI research during this time. The effort has faced a number of challenges, including limited human subject basic and translational research, limited epidemiological data on combat-related injuries, limited capacity and standards for data acquisition, and a lack of standardized evidenced-based protocols for treatment. All these areas have undergone significant growth and development, leading to the comprehensive system of care present today. A further challenge in this patient population has been the clinical co-morbidity of TBI, post-traumatic stress disorder, and chronic pain syndrome. The Army and the DoD have created treatment programs that are interdisciplinary in clinical approach, targeting particular neuropsychological domains of dysfunction rather than diagnostic category or etiology of injury. This article presents the history of this effort, the challenges to accurate and adequate diagnosis and care that remain, and the future of brain injury clinical and research efforts in the military. Copyright © 2013 John Wiley & Sons, Ltd.