The specific aim of this study is to compare, by means of a randomized clinical trial, the efficacy of three surgical treatment combinations: adenoidectomy with myringotomy (A-M), adenoidectomy with myringotomy and tympanostomy tube insertion (A-M&T), and M&T alone, in reducing subsequent middle ear disease in children aged 24-47 months with otitis media with effusion (OME) of at least 3 months' duration unresponsive to standardized, recent antimicrobial treatment. The children are randomly assigned to one of three treatment arms: 1. M&T; 2. A-M; and 3. A-M&T. Subjects are be stratified according to: 1. age; 2. nasal obstruction; and 3. previous tubes. All subjects are scheduled for surgery according to assignment within 4 weeks after entry. The first post-operative visit takes place 2 weeks after surgery, and a complete examination of the ears, nose, and throat (ENT exam) including pneumatic otoscopy, tympanometry and audiometry is performed. Subjects are followed with monthly evaluations (ENT-exam, pneumatic otoscopy, tympanometry) for three years. Audiometry is performed every 6 months. All subjects are evaluated at any time while still enrolled in the study if signs and symptoms of URI, acute otitis media (AOM, including otorrhea), or OME occur and are treated appropriately. Subjects who develop OME for 4 months bilaterally or 6 months unilaterally have M&T and continue to be followed in the study. The primary outcome measure will be percentage of time with middle ear effusion (MEE). Episodes of AOM, otorrhea, and OME, time to first recurrence, and number of surgical procedures will be compared between the three treatment groups. Treatment failures, complications and sequelae of treatments will also be recorded and compared among the three treatment groups.