A total of 82 patients involving 83 episodes of proven or presumed bacterial infection were treated with sulbactam/ampicillin. These included 36 cases of soft tissue infection or abscess, four cases of joint or bone infection, 20 cases of respiratory tract infection (17 cases of pneumonia, two of otitis media, and one of tonsillitis), 15 urinary tract infections, three cases of enterocolitis, one case of infective endocarditis, two cases of septicemia, and two of peritonitis. The causative pathogen was isolated in 48 cases (49 infections). These pathogens included Staphylococcus aureus 13 cases, Staphylococcus epidermidis one, Streptococcus pyogenes two, Streptococcus pneumoniae two, Viridans group streptococcus two, peptostreptococcus one, Haemophilus influenzae one, Escherichia coli 12, Enterobacter cloacae three, Proteus mirabilis one, Acinetobacter calcoaceticus one, Salmonella spp. two, Shigella sonnei one, Bacteroides fragilis one, and polymicrobial infections of various combinations in five cases. No bacterial pathogens were isolated in 34 infections, 14 cases of pneumonia and 15 soft tissue infections. Sulbactam/ampicillin was given by intravenous bolus in a dosage range of 75-450 mg/kg/day in four divided doses for variable periods of time depending on the type and severity of the infection. Of a total of 83 episodes of infections, 80 (96.4%) cases were either cured or improved. Bacteriologic eradication also occurred in 46 (93.9%) of 49 infections. Side effects were diarrhea in two patients, acute hemolytic anemia in one patient, and transient elevations in SGOT and leukopenia in one patient. Side effects disappeared upon completion of treatment. Sulbactam/ampicillin is a safe and effective antibiotic for the treatment of common pediatric infections.