In NSW, hepatitis C has been the subject of specific surveillance and prevention programs for many years. Despite this experience and significant investment, there remain challenges both in understanding the epidemiology of this virus and in implementing effective prevention programs. This study aimed to enhance the public health surveillance program and contribute to the evidence base for hepatitis C prevention in NSW. The aim of Phase One was to develop and trial a methodology for an ongoing program of enhanced surveillance of hepatitis C virus (HCV) in NSW. Phase Two aimed to increase understanding of the practices, settings, networks and structures contributing to HCV infection.