Twenty patients with advanced liver disease, in need of transplantation, were given three injections of 20 micrograms and three injections of 40 micrograms hepatitis B vaccine to see if an antibody response could be obtained. Only 20% of patients developed measurable anti-HBs. One who failed to develop anti-HBs developed chronic hepatitis B after exposure to her infected sexual partner. Type of liver disease in the native liver, age, sex, sexual preference, timing of immunization (before or after transplantation), and dosage of hepatitis B vaccine did not seem to explain the lack of immunologic response to hepatitis B vaccine. It is presumed that immunosuppression, both from the underlying disease and from immunosuppressive medications, best explains our findings. Liver transplantation patients infrequently benefit from hepatitis B vaccine. It is possible that other vaccines given to prevent viral and bacterial illness may also fail to elicit immunologic response in such patients.