Chronic infections caused by hepatitis C virus affect hundreds of millions of people worldwide and may lead to life-threatening conditions like cirrhosis and cancer. New safer and more effective therapies are needed to prevent the end stage liver diseases that cause one million hepatitis-related deaths a year. The scid/Alb-uPA mouse carrying a chimeric liver with implanted human cells is the only small animal model of hepatitis C replication. This contract utilizes this animal model to evaluate candidate therapeutic compounds. Antiviral compounds evaluated can include small molecule drugs, antibodies and RNAi.