The number of patients with end stage liver disease is growing worldwide. This is likely a result of advances in medical science that have allowed these patients to lead longer lives since the incidence of diseases such as alcoholic cirrhosis and viral hepatitis have remained stable or even decreased in recent years, at least in more developed nations. Many of these patients will require anesthetic care at some point. The understanding and application of basic principles of pharmacokinetics is paramount to the practice of anesthesia. An understanding of pharmacokinetic principles provides the anesthesiologist with a scientific foundation for achieving therapeutic objectives associated with the use of any drug; however, pathologic conditions often alter the expected kinetic profile of many drugs. Anesthesia providers caring for these patients must be aware of the altered pharmacokinetics that may occur in these patients. We review normal liver physiology, pathophysiology of liver disease in general, and how liver failure affects the pharmacokinetics and pharmacodynamics of anesthetic agents; providing some specific examples.