Acoustic rhinometry (AR) and rhinomanometry (RMM) study two different parameters of nasal ventilation: respiratory function and the anatomy of nasal cavities. This article looks at their usefulness, in particular in the surgical field. We list the normal values for these tests. Nasal obstruction is a symptom of multifactorial origin. Nasal patency is only one factor influencing the sensation of nasal ventilation. Despite the range of divergent opinions in both the literature and among rhinological clinicians, the objective assessment of nasal patency in functional rhinoplasty or septorhinoplasty seems to be advisable. The roles of AR and RMM still have to be established.