A study comparing otoscopy with tympanometry was carried out in 1702 ears in seven- and ten-year-old children. Pneumatic otoscopy in 917 ears showed an 88 per cent agreement with tympanometry. The agreement was better in ears considered normal by the otoscopist than in ears that were considered abnormal. Furthermore, the accuracy of otoscopy was better in the older children than in the younger ones. A procedure employing simple otoscopy in 785 ears gave an 83 per cent agreement, but in about 15 per cent of these ears the examiner felt unable to base his evaluation on certainty. It was found that a middle-ear pressure of -100 mm. H2O correlated with recognizable pathology when pneumatic otoscopy was performed.