The diagnostic investigation of allergic rhinitis requires nasal provocation. Subjective signs of such an allergy are secretion, irritation (itching and sneezing), and swelling of the nasal mucosa. Mainly the latter can be determined objectively, by measuring the change in nasal airway resistance using rhinomanometry. We shall discuss the current method which is especially suitable for determining nasal allergies in children. The results of 69 allergic and 22 healthy subjects investigated with the oscillation method will be presented.