Hepatitis B is the most important of several hepatitis viruses of man because of the number of cases of the disease and the frequent occurrence of persistent infection that may lead to cirrhosis and cancer of the liver. The pathology of hepatitis B infection results mainly from the self-destructive cytotoxic T cell response of the host. This may be modulated by soluble pre-core e antigen of the virus that induces immune tolerance and by cytokines elaborated by cytotoxic T cells, which suppress viral replication in the infected cell. Pathogenesis of the disease is markedly influenced by viral mutations. Persistent hepatitis B virus infection may be controlled in a minority of patients by passive α-interferon therapy, and in a majority of patients by the nucleoside lamivudine until resistance develops. The best means to control the disease is by prevention through application of the highly effective vaccine prepared using surface antigen of the virus. It is anticipated that the gradually increasing application of the vaccine throughout the world may lead to elimination of hepatitis B as an important medical problem. This paper is intended to provide a cursory overview of the contemporary knowledge relating to pathogenesis, prophylaxis and therapeusis of human hepatitis B.