The results of vaccination against hepatitis B among health-care workers in "Sestre Milosrdnice" University Hospital are presented. Out of 1884 health-care workers 920 (48.8%) were tested for serum HbsAg, as well as anti-HBs and anti-HBc antibodies. There were 111 (12.1%) persons with one or more positive HBV markers. Seven of them (0.8%) were HBV (HbsA-positive) carriers, and 104 (11.3%) had positive anti-HBc and/or anti-HBs. A significant difference of frequency of positive HBV markers between women and men was not found using the chi 2 test for statistical analysis. The vaccination was started in 583 (72.1%) out of 809 examinees with negative HBV markers, out of which 339 (41.9%) received complete three doses and 244 (30.2%) only one or two doses of vaccine. Even 226 (27.9%) persons susceptible to HBV infection refused the vaccination, and other 244 (30.2%) examinees did not receive the complete vaccination course. Therefore, the pre-testing showed that in 12.1% of examinees there was no need for vaccination, which means the saving of 333 bottles of vaccine. Totally 470 health-care workers out of 809 liable to HBV infection were not protected by this action, in full 58.1%! Out of 1884 health-care workers in "Sestre Milosrdnice" University Hospital even 964 (51.2%) refused the testing.