The effect of orthodontic treatment on airway dimensions is still debatable. Multiple factors have been associated with reduced oropharyngeal dimensions with reduction in the space between the mandibular body and cervical column leading to respiratory dysfunction. This text book provides evidence based literature on the various etiological factors of narrow airways. It also highlights the treatment of reduced pharyngeal dimensions with least aggressive approach using a variety of removable orthodontic appliances. The writing can significantly help the otolaryngologists and the orthodontists in treating patients with different levels of airway obstruction.