Quantitative structure-activity relationship (QSAR) is an important drug design approach to understand the relationship between the chemical structure and their biological activity. The book describes brief introduction to hepatitis C virus (HCV), life cycle, identified targets and current progress towards development of anti-HCV agents. 2D and 3D-QSAR studies for anti-HCV compounds from different categories targeting NS5B polymerase have been incorporated. Some of the selected categories are nucleoside and non-nucleosides.