Concussion is a hot topic in the media and on many people's minds, particularly in terms of sports-related brain injuries. This presentation will review what we know and do not know about concussion: Its acute effects, recovery, risks, and association with cognitive disorders later in life. This will include a review of recent studies of retired professional athletes with a history of concussion utilizing brain imaging, diagnostic, and neurobehavioral assessment techniques. Additional topics will include traumatic brain injury as a risk factor for the later development of cognitive impairment and dementia.