One of the most important factors in the diagnosis of allergic diseases of the nose is the history, which requires a detailed knowledge of the allergic disease, and of the personal and occupational environment of the patient. Skin tests usually confirm the allergens suggested by the history. If this is not the case, a further history must be taken with respect to the agents identified by the positive skin tests. Other additional investigations must be performed such as RAST, the human basophil degranulation test, the histamine liberation test and the intranasal provocation test (IPT) with anterior rhinomanometry. The guidelines of the working group on bronchial and nasal provocation tests of the German Society for Research into Allergy and Immunity for the performance of the IPT should be respected because they are reproducible and standardised.