There has been increasing awareness of the incidence and potential long‐term consequences of mild traumatic brain injury (mTBI) in children and young adults. While parents, school systems, and athletic programs are clamoring for evidence‐based guidelines, the field remains primitive in understanding the factors resulting in a spectrum of individual outcomes, most of which are complete, but some of which are not. In this article, we discuss the definition, epidemiology, clinical presentation, course, and outcomes of mTBI, with a focus on the pediatric population as the context for reviewing the mechanisms and pathophysiology mediating, and biomarkers reflective of, more significant concussion‐induced brain injury. Our goal is to present a general overview of the features of mTBI in the pediatric population in order to provide a conceptual model for pediatricians and pediatric subspecialists. This model emphasizes the importance of establishing actionable, noninvasive biomarkers that are reflective of brain injury and that may identify those pediatric patients who can benefit from earlier and more aggressive interventions. We will focus on the specific features of mTBI in pediatric patients; although given the relative lack of research in the pediatric population, we will also extrapolate from research on adults.