Obstructive sleep apnea syndrome is characterized by recurrent total or partial upper airway collapse during sleep. Although this disease affects more than 5% of general population, it remains largely undiagnosed. It is associated with an increase in cardiovascular risk and with a decrease in sustained attention that may cause automobile accidents or occupational injuries. Several simplified diagnostic tools (polysomnography) now allow easier diagnosis in a sleep laboratory or on an outpatient basis. Nasal continuous positive airway pressure remains the reference treatment, acting as a pneumatic splint that maintains airway patency. CPAP is effective in reducing daytime somnolence and controlling cardiovascular risk. Prosthetic management is an alternative to CPAP in cases of moderate sleep apnea with or without retrognathism in normal-weight patients. The effectiveness of surgery has not been proven, and it is indicated only in exceptional cases.