Rhinomanometry is a functional test of nasal aerodynamics that measures transnasal airflow and the pressure gradient allowing nasal resistance to be calculated from these data. Three methods of rhinomanometry that are currently in use are anterior rhinomanometry, posterior (peroral) rhinomanometry and postnasal (pernasal) rhinomanometry. The usefulness of this method has increased owing to the development of technology and use of microcomputers connected to the measuring devices. Rhinomanometry can be used for: clinical evaluation of the symptom of nasal obstruction; research in nasal physiology; allergy challenge testing; pre- and post-treatment assessments of surgical or medical therapy; and evaluation of patients with sleep apnea.