Rhinoplasty can both improve the appearance of your nose and the breathing through your nose.  There are several common reasons why you may have difficulty breathing through your nose; a deviated septum, traumatic injury,  enlarged internal components, and internal or external valve collapse.  Fortunately all of these issues can be addressed at the time of a nose job.  Sometimes due to the natural way that your septum developed it can have a severe curvature or warp that can totally block or partially block your nasal airways.  The septum is like a rudder on a ship, if deviated can be the cause of a crooked nose.  Trauma to the nose can cause an injury to the bone and/or cartilages that weakens, collapses, or severely deforms them resulting in blocked nasal passages.  The internal valve is like a tent that keeps the middle part of the nose open (much like a breath right strip) and the external valve is the structural part that keep your nostrils open.  All of these components of the nose can  be corrected during rhinoplasty with specific techniques that can improve your nasal breathing.  These procedures that improve the function of your nose are often covered by insurance. –FRN