The association between HBV, immune complexes, and extrahepatic tissue damage has been studied intensively. Still, many links are missing in our understanding of this complex set of interactions. Although the conclusion is inescapable that several extrahepatic features of HBV are mediated by immune complex injury, several of the associations are debatable, and we know very little about how and why such injury occurs. In most instances, the presence of circulating immune complexes in HBV infection is probably of no pathogenic importance but may be related to normal mechanisms of immune clearance of virus antigens.