These volumes offer both new and experienced investigators an encyclopedic collection of powerful tools for studying HBV and HDV infections, as well as an essential resource for finding new therapies to treat chronically infected patients. In the first volume, the authors focus on readily reproducible molecular methods for the identificationa and qualification of viral markers, the detection and impact of viral variants, and the study of the viral life cycle. In the second volulme, the authors focus on protocols for the study of host immune responses to infection, in vitro and in vivo models of infections, and the development of antivirals.