This application is a second revision originally submitted on September, 1988 and resubmitted on September, 1989. The objectives of this study are to determine: (1) whether otitis media with effusion (OME) occurring at common levels of frequency and duration during the first three years of life causes lasting impairments in speech, language, cognitive and psychosocial development; and (2) whether prompt tympanotomy-tube placement (TTP) is efficacious in preventing or lessening the impairments. Two null hypotheses are proposed: (1) that children with lesser cumulative durations of OME during the first three years of life will achieve scores on certain designated tests at ages 3 through 7 years which are no more favorable than the scores of children with greater cumulative durations of OME (within specified upper limits) during the first three years of life; (2) that children with OME during the first three years of life who are managed with tympanotomy-tube placement (TTP), if divided randomly into two groups which receive: (a) prompt TTP; or (b) delayed TTP will show scores on certain designated tests which are not significantly different between the two TTP groups. A total of 5,338 healthy infants less than two months of age will be enrolled in a prospective study over a 21-month period. Middle ear status will be monitored monthly during the first two years of life, bimonthly during the second year and quarterly thereafter by means of tympanometry and pneumatic otoscopy. Hearing levels will be monitored monthly in children who develop persistent otitis media with effusion. Children who meet specific criteria for persistent OME during the first three years of life will, subject to parental consent, be randomly assigned to receive TTP either promptly (early TTP) or after a defined period if OME is still present (late TTP). Developmental outcomes will be assessed in all subjects at ages 2 months, 1 year and 2 years through standardized questionnaires. Speech, language, cognitive and psychosocial development will be assessed in all early TTP and late TTP subjects and in a sample of remaining subjects at ages 3, 4, 5, 6 and 7 years using standardized tests.