Pharyngeal pH monitoring and laryngoscopy are routinely used to diagnose gastroesophageal-laryngeal reflux as a cause of respiratory symptoms. Although their use seems intuitive, their ultimate diagnostic value is yet to be defined. We studied 10 asymptomatic (control) subjects and 76 patients with respiratory symptoms. Both patients and control subjects were given a symptom questionnaire. Each underwent direct laryngoscopy using the reflux finding score (RFS) to grade laryngeal injury, esophageal manometry, and 24-hour esophagopharyngeal pH monitoring. The patients were then classified as RFS+, if the score was greater than 7, and pharyngeal reflux (PR)+, if they had more than one episode of PR detected during pH monitoring. The most common symptoms reported by patients were hoarseness (87%), cough (53%), and heartburn (50%). Control subjects had a significantly lower RFS (2.1 vs. 9.6, P < 0.01) and fewer episodes of PR (0.2 vs. 3.4, P < 0.01), than patients. None of the control subjects had more than one episode of PR during a 24-hour period. Fifty patients (66%) were RFS+ and 26 (34%) were RFS-. Thirty-two patients (42%) were PR+ and 44 (58%) were PR-. Fifteen patients had a normal RFS and no PR (group I = RFS-/PR-). Forty patients had discordance between the laryngoscopic findings and the pH monitoring (group II = RFS-/PR+ or RFS+/PR-). Twenty-one patients had both an abnormal RFS and PR (group III = RFS+/PR+). Patients in group III had significantly higher heartburn scores and distal esophageal acid exposure. Eighty-three percent of patients in group III but only 44% in group I improved their respiratory symptoms as a result of antireflux therapy. An abnormal PR or RFS differentiates patients with laryngeal symptoms from control subjects. Agreement between PR and RFS helps establish or refute the diagnosis of gastroesophageal reflux as a cause of laryngeal symptoms. Patients who are RFS+ and PR- may have laryngeal injury from another source, whereas patients who are RFS- and PR+ may not have acid entering the larynx, despite the presence of PR. Patients who are RFS+ and PR+ have more severe gastroesophageal reflux disease and their reflux causes laryngeal damage. Laryngoscopy and pharyngeal pH monitoring should be considered complementary studies in establishing the diagnosis of laryngeal injury induced by gastroesophageal reflux. ( J GASTROINTEST SURG 2002;6:189-194.)