Minimum inhibitory concentration testing is the most common standard used to evaluate antibacterial activity of antimicrobials against specific pathogens. The consideration of pharmacodynamic factors in conjunction with these tests can improve the management of bacterial infections. Further, the incorporation of MIC values into pharmacodynamic ratios may provide clinically useful tools for selecting optimal antibiotic selection, determining proper dosing strategies, and predicting therapeutic outcomes. Physiologic consequences of infection and antibiotic treatment, such as endotoxin release and initiation of the septic cascade, also must be considered when choosing appropriate anti-infective therapy. The introduction of adjuvant immunotherapy, along with improvement, validation, and implementation of pharmacodynamic predictors of antibiotic efficacy, undoubtedly will provide the medical community with an effective arsenal to further reduce the morbidity and mortality rates associated with bacterial infections.