Indications and results of corrective nasal surgery are at times uncertain with the traditional clinical evaluation. To find more certain parameters a study was made with active anterior computerized rhinomanometry (C.R.) pre- and post-operatively in 50 patients randomly chosen from those proposed for rhinoseptoplasty during 1990. The level of total basal resistance (TR) and total residual resistance after pharmacological decongestion were used as objective indicators of respiratory stenosis. Clinically these patients showed some degree of nasal deformity, usually associated with septal deviation. Difficulty in breathing did not always correspond to the level of TR recorded. At times habit or psychological factors related to nasal aesthetics could play an important role. Using CR it was possible to divide the patients into three categories: a) the first (9 patients with normal total basal resistance) required treatment for exclusively aesthetic reasons; b) the second (18 patients with increased basal TR but normal residual TR) required treatment of the conchae and medical therapy; c) the third (23 patients with increased basal and residual TR) had the broadest functional and aesthetic indications. Six months after surgery normal residual TR was found in 96% of these cases. Only 12% of the patients were functionally unsatisfactory, with residual anatomical alteration (4%), phlogosis (4%) or sensations "sine materia" (4%). The present experience confirms the value of CR as an objective test for surgical selection and functional results.