Concussion is a disturbance in brain function caused by direct or indirect force to the head. It is a functional rather than structural injury that results from shear stress to brain tissue caused by rotational or angular forces-direct impact to the head is not required. Initial evaluation involves eliminating cervical spine injury and serious traumatic brain injury. Headache is the most common symptom of concussion, although a variety of clinical domains (e.g., somatic, cognitive, affective) can be affected. Signs and symptoms are nonspecific; therefore, a temporal relationship between an appropriate mechanism of injury and symptoms must be determined. There are numerous assessment tools to aid diagnosis, including symptom checklists, neuropsychological tests, postural stability tests, and sideline assessment tools. These tools are also used to monitor recovery. Cognitive and physical rest are the cornerstones of initial management. There are no specific treatments for concussion; therefore, focus is on managing symptoms and return to play. Because concussion recovery is variable, rigid classification systems have mostly been abandoned in favor of an individualized approach. A graded return-to-play protocol can be implemented once a patient has recovered in all affected domains. Children, adolescents, and those with a history of concussions may require a longer recovery period. There is limited research on the management of concussions in children and adolescents, but concern for potential consequences of injury to the developing brain suggests that a more conservative approach to management is appropriate in these patients.