A concussion is a serious injury and should not be taken lightly. It is a type of traumatic brain injury, or TBI, that can be caused by a bump, blow or jolt to the head that can change the way your brain normally works. They can also occur from a blow to the body that causes the head to move rapidly. Even a mild bump or blow to the head can be serious. Unfortunately, concussions can be difficult to diagnose, in part because the symptoms can be subtle and may not show up for hours or even days. For these reasons, it is key that parents, coaches and athletes take time to understand what concussions are and their potential consequences, recognize concussion signs and symptoms, know how to respond, and learn the steps for returning to activity after a concussion. If you suspect an athlete has a concussion, keep the athlete out of play (when in doubt, keep them out). The athlete must be evaluated by a health care professional experienced in evaluating concussions to assess the severity of the concussion, the path to recovery and the steps to return to play.