The protective efficacy of three schedules of a recombinant hepatitis B vaccine was evaluated in 42 patients undergoing dialysis at a teaching hospital. The rate of seroconversion after vaccination was highest (82.3%) among the recipients of three 20-micrograms doses (i.e. double the conventional dose for healthy adult) at 0, 1 and 2 months (group II). The response was satisfactory (80%) among the recipients of three 20-micrograms doses at 0, 1 and 6 months (group III) but was lowest with the single dose schedule of three 10-micrograms doses at 0, 1 and 2 months (group I). Seroconverters from all the three groups received a booster dose (each equal to his scheduled dose) at 12 months. Those who did not seroconvert from groups I and II were shifted to group III. The rate of seroconversion was higher in female (88.9%) than in male patients (66.7%) and in younger patients less than 30 years (83.3%) than in elderly patients more than 50 years. Patients undergoing peritoneal dialysis also responded much better (93.3%) than the hemodialysis patients (66.7%). In conclusion, a schedule of double the conventional dose of the vaccination for healthy adults at 0, 1, 2, and 12 months seems to give a better seroconversion and higher response to the HB vaccine, but a further large-scale study is needed to confirm this finding and also to look into the difference in response between male and female, younger and older patients and the difference in response between HD and PD patients.