Current understanding of the term "concussion" is fraught with misconceptions regarding the extent and nature of brain injury. Despite increasing attention in popular media and within the context of sports, considerable gaps exist in our knowledge of the diagnosis, underlying brain pathology, recovery of function, and optimal interventions for concussion. In this special interest article, we discuss the definition and risk factors associated with concussion, summarize and highlight some of the most widely used assessment tools, and critique the evidence for current principles of concussion management. Our evaluation has identified opportunities for novel neuroimaging techniques to improve the understanding of the pathophysiology of concussion and to evaluate the changes in the recovering brain in response to rehabilitation. In summary, a clear definition of the underlying brain pathology, the potential long-term consequences, and the risk factors of injury and recovery will help guide future research aiming to minimize the impact of injury and develop innovative and successful therapeutic approaches aimed at ameliorating the functional impairments associated with concussion.