Hepatitis B reactivation associated with immune suppressive and biological therapies is emerging to be an important cause of morbidity and mortality in patients with current or prior exposure to hepatitis B virus infection. The population at risk for HBV reactivation includes those who are either currently infected with HBV or have past exposure to HBV. Since curative and eradicative therapy for HBV is not currently available, there is a large reservoir of individuals at risk for HBV reactivation in the general population.