The escalation of serious infections in critically ill patients over the past 25 years has continued despite advances in contemporary medicine. Ongoing research to reduce the high morbidity and mortality rates is mandated. beta-lactam antibiotics are often used empirically in serious infections. The efficacy of these time-dependent antibiotics is correlated with the time that concentrations are maintained above the minimum inhibitory concentration of the infective pathogen. In critically ill patients, pathophysiological changes can reduce antibiotic concentrations and thus alternative modes of administration such as continuous infusion have been studied and shown to standardize beta-lactam pharmacokinetics and meet pharmacodynamic targets. Clinical data supporting the efficacy of continuous infusion are currently scarce, but data continue to grow. Likewise antibiotic resistance continues to grow. Recent data suggest that poor dosing strategies may be contributing to this problem, which is exacerbated by a lack of development of alternate antibiotics. Suffice to say clinicians must use antibiotic regimens that optimally treat the individual patient and reduce the development of antibiotic resistance.