Mild traumatic brain injury is frequently seen in an athletic population, especially in contact sports. Many underlying pathophysiologic mechanisms have been identified. Several injury classification schemes have been proposed, yet severity grading and management remain controversial. Although second-impact syndrome is the driving force behind conservative management by many clinicians, athletes suffer more commonly from postconcussive syndrome. Recent research has examined the diagnostic value of several available tests, including electroencephalogram, magentic resonance imaging, and neuropsychologic testing, with variable results. Neuropsychologic testing has shown promise in evaluating cognitive function when baseline studies are obtained and compared with postinjury examinations. Treatment of postconcussive symptoms with selective serotonin reuptake inhibitors has also been tested, with favorable results.