A review of 34 patients presenting with acute mastoiditis was undertaken. Prior treatment was noteworthy for lack of medical or surgical drainage at the time of initial otitis media. Typical findings, in hospital, included postauricular edema and tenderness, displaced auricle, and distorted tympanic membrane. X-rays were not diagnostic, nor were they helpful in determining who was a surgical candidate. Treatment was individualized. Patients with obvious subperiosteal abscesses, and those who did not respond rapidly to enteric antibiotics, underwent early mastoid surgery. The remaining patients received enteric antibiotics, had drainage established, and were carefully followed. Most resolved without mastoid surgery. Patients with a history of antecedent ear disease were examined separately from those without such history. The former group required mastoid surgery more often than the latter and had poorer outcome.