Ticarcillin disodium/clavulanate potassium and other beta-lactamase inhibitor/penicillin combinations have been recognized recently as broad-spectrum drugs that have a major role in chemotherapy for serious surgical sepsis. Their spectrum of activity allows the economical substitution of ticarcillin disodium/clavulanate potassium for anaerobe-active cephalosporins and for the traditionally used combination of clindamycin and an aminoglycoside. Indeed, the ticarcillin disodium/clavulanate potassium spectrum was judged to be broader than that of the other agents while maintaining comparable or superior clinical efficacy and safety. The beta-lactamase inhibitor combinations have also proven their economical application to the prevention of infections after trauma and elective surgery, although those indications have not been well accepted. The timing seems to be right for the expanded use of these combinations in order to lower therapeutic and prophylactic costs. This concept is concurrent with the critical assessment of the cost effectiveness, safety and usable spectrum of older therapeutic regimens. However, some of the traditional nonpenicillin treatment modalities must be maintained for those patients with a penicillin allergy.