1. Hepatitis C is a global health problem affecting over 170 million people worldwide. 2. There is wide geographic variation in both prevalence and genotype distribution of hepatitis C virus on a global level. 3. Most hepatitis C virus is spread parenterally, either through intravenous drug use or, in lesser-developed countries, through blood contamination during medical procedures. 4. Hepatitis C is a leading cause of end-stage liver disease and hepatocellular carcinoma. 5. Despite a declining incidence of new infections, the burden of disease, both in terms of mortality and in terms of cost, is expected to increase over the next decade.