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