Effective antimicrobial chemotherapy integrates pharmacology and microbiology to achieve the most favorable clinical and microbiologic outcomes. Understanding such relationships allows us to select the optimal drug dose in a rational manner. The difficulty lies in translating the research findings to clinicians at the bedside. Current clinical practices have not embraced fully many advances in pharmacokinetic/pharmacodynamic research. This article summarizes what we have learned over the past decades and highlights some of the barriers to translating these results into clinical practice. Reducing these barriers would help to bring clinically relevant laboratory work to the bedside and would emphasize evidence-based medicine. It may also improve patient outcomes and minimize the emergence of resistance.