Obstructive sleep apnea is a significant medical problem affecting up to 4 percent of middle-aged adults. The most common complaints are loud snoring, disrupted sleep and excessive daytime sleepiness. Patients with apnea suffer from fragmented sleep and may develop cardiovascular abnormalities because of the repetitive cycles of snoring, airway collapse and arousal. Although most patients are overweight and have a short, thick neck, some are of normal weight but have a small, receding jaw. Because many patients are not aware of their heavy snoring and nocturnal arousals, obstructive sleep apnea may remain undiagnosed; therefore, it is helpful to question the bedroom partner of a patient with chronic sleepiness and fatigue. Polysomnography in a sleep laboratory is the gold standard for confirming the diagnosis of obstructive sleep apnea; however, the test is expensive and not widely available. Home sleep studies are less costly but not as diagnostically accurate. Treatments include weight loss, nasal continuous positive airway pressure and dental devices that modify the position of the tongue or jaw. Upper airway and jaw surgical procedures are necessary in selected patients.