Passive anterior rhinomanometry used for nasal provocation tests in respiratory allergology is a very easy test to perform. On the basis of five years' experience, the authors analyse their opinion concerning this technique and review the value of nasal challenge tests in allergic rhinitis. The only real problem is that of the quality of the allergen used, this being the essential factor in terms of correlation with other diagnostic tests (for D.P.: 66.6% between challenge test and skin tests, and 78.5% between challenge test and RAST). Indications are very wide and the results of nasal challenge provide a substantial diagnostic argument when taking therapeutic decisions. However it cannot serve as a substitute for the bronchial challenge test in cases of combined rhinitis and asthma since there are differences in sensitivity and reactivity between the nasal and bronchial mucosae.