A retrospective study was performed in 117 children with head and neck space infections treated at the Children's Hospital of Pittsburgh from January 1986 through June 1992, Peritonsillar space infections were the most common (49%), followed by retropharyngeal (22%), submandibular (14%), buccal (11%), parapharyngeal (2%), and canine (2%) space infections, The most common pathogens isolated (N = 78) were the aerobes beta-hemolytic streptococcus (18%) and Staphylococcus aureus (18%), the anaerobes Bacteroides melaninogenicus (17%) and Veillonella (14%), and the gram-negative organism Haemophilus parainfluenzae (14%), beta-Lactamase production by aerobic pathogens was detected in 22% of cultures, Computed tomography scans (N = 16) were reviewed in blinded fashion and compared with operative findings. The sensitivity of computed tomography scan in detecting the presence of an abscess vs, cellulitis was high (91%), whereas the specificity was rather low (60%), Treatment of head a nd neck space infections in children should consist of accurate physical diagnosis aided by imaging studies, empiric antibiotic therapy that covers gram-negative and beta-lactamase-producing organisms as well as gram-positive organisms and anaerobes, and timely surgical intervention, when indicated.