Psychiatric symptoms following concussion are prevalent and associated with a plethora of negative consequences including elevated post-concussive symptoms, cognitive disturbances, and poorer quality of life. With a primary focus on depression and post-traumatic stress disorder (PTSD), this chapter provides an overview of factors relating to the diagnosis, treatment, and neurobiology of post-concussion psychiatric disorders. First, the prevalence and clinical correlates of depression, suicidality, anxiety disorders, and PTSD following concussion are outlined. Second, evidence-based treatment recommendations for post-concussion depression and PTSD are summarized, including the use of selective serotonin reuptake inhibitors (SSRIs) and cognitive behavioral therapy. The currently available evidence suggests no substantial differences in the management of post-concussion depression and PTSD as compared to those occurring in the absence of concussion; however, caution should be exercised with pharmacological agents post-concussion to avoid exacerbating existing physical or cognitive symptoms with medication-related side effects. Consideration should also be given to other situational or psychosocial stressors that may co-occur with the injury and ensure they are addressed in tandem with clinical symptoms. Third, this chapter highlights progress in identifying biomarkers of psychiatric disorders following concussion, including genetic, inflammatory, and neuroimaging markers associated with psychiatric symptoms following injury. Finally, challenges associated with research on neuropsychiatric sequelae of concussion are discussed, including the overlap in symptoms between psychiatric disorders and “post-concussive syndrome” and issues of diagnostic clarity. The significant heterogeneity in sample characteristics across studies, many of which are cross-sectional, limits progress in understanding the time course and trajectories of psychiatric symptoms post-concussion. Suggested future directions include longitudinal studies of psychiatric outcomes post-concussion, as well as examinations of psychiatric disorders with and without concussion history in an effort to disentangle these complex relationships.