Before the invention of CPAP therapy, the only effective surgical treatment for obstructive sleep apnea syndrome was tracheotomy. Now, surgical approaches mainly focus on two anatomical sites. Each procedure influences either the retropalatal or retrolingual portion of the pharynx. They might be applied individually, synchronously with other procedures, or sequentially with other therapeutic devices. Common methods of velar surgery include uvulopalatopharyngoplasty (UPPP), Laser-assisted uvuloplasty (LAUP), radiofrequency or uvulaflap. These techniques are indicated mainly in patients with mild OSAS. Other procedures focus on the posterior airway space (PAS), including operations that reduce the volume of the tongue or base of tongue. In selected patients, an enlargement of the retrolingual airway is gained by osteosynthetic techniques. Improvement of the nasal airway passage is gained by performing a septoplasty and/or conchotomy. In this paper, the different methods and their indications for surgical therapy will be explained and the results are summarized.