Obstructive sleep apnea is a chronic respiratory disorder characterized by repetitive episodes of upper airway obstruction. It is caused by various anatomic and physiological factors such as those related to muscle tone, small mandible, obesity, alcohol etc. With the increasing awareness of sleep apnea among the individuals now-a-days, it becomes important for an Orthodontist to have a thorough knowledge about the signs and symptoms of the condition and its management. This article brings about a brief review of few basic aspects of this disorder, diagnosis and treatment modalities.