Signs and symptoms of concussion—a functional injury resulting from a direct or indirect force to the head—can vary greatly from one case to another, with headache being the most common symptom. Other symptoms may include dizziness, balance issues, and disorientation. Although loss of consciousness was once considered a main sign of concussion, modern medicine has since revealed that this occurs in less than 10% of patients. Because there is no defined treatment that applies to all concussion cases, medical professionals must treat concussion patients on a case-by-case basis using their best clinical judgment. There are a variety of diagnostic tools available to aid in the identification and assessment of concussion signs and symptoms, including symptom checklists, neuropsychological tests, postural stability tests, and sideline assessment tools. Clinicians also can use these tools to monitor a patient’s recovery from concussion. The first step in any concussion evaluation is eliminating spinal injury or serious brain injury as causes of the symptoms the patient is experiencing. If concussion is still suspected, patients typically will begin a period of cognitive and physical rest, as activity could delay recovery or make symptoms worse. Once symptoms subside and the patient has stopped taking medication that could mask those symptoms, he or she can return to normal activity on a gradual basis. He or she should undergo a follow-up re-evaluation several months later to verify full recovery.