The project with which we are most concerned at present is the relation of hepatitis B to primary hepatic carcinoma (PHC), and methods for the prevention of the disease. PHC is the most common cancer in men in many parts of Africa and Asia. For many years investigators in Africa including Payet (40), Davies (41), and Steiner (42) have suggested that hepatitis could be the cause of PHC. With the availability of sensitive tests for Australia antigen it became possible to test this . hypothesis; it has now been established that there is a striking association of hepatitis B with PHC (43, 45) (Table 1).