Between 1971 and 1978 the author did 575 rhinomanometric examinations, using the Cottle rhinomanometer, Model FP-102. It was always a unilateral passive rhinomanometry. Results obtained on the rhinomanometer were compared with the patient's history and the clinical examination. For 423 cases (74%) the rhinomanometry confirmed the clinical data, and for 152 cases (26%) there was no relation between the two. It is concluded that for evaluation and choice of treatment the clinical history and examination are the only valuable criteria. Defects of the rhinomanometer are discussed. In medical rhinitis an effect was noticed which was exactly the contrary to that expected with a local decongestant. We believe that this equipment is not sufficiently developed to be currently useful in clinical work although rhinomanometry may have a role in research.