Taiwan initiated a nationwide program in 1986 to have all 15-year-old schoolgirls vaccinated against rubella and another program in 1992 to encourage all women of childbearing age to receive rubella vaccination. To assess the immunity among women after the implementation of these programs, we conduct a serosurvey. We recruited women who were 15-44 years old and received pre-employment health examinations at the clinic of an industrial park from January 1 to June 30, 2000. Anti-rubella antibody titers were determined by enzyme-linked immunoassays. All 1,087 women who fit the selection criteria agreed to participate, and the overall susceptible (seronegative) rate was 5.7%. The susceptible rate was much lower among women who were covered by both programs than women who were not (4% versus 23%, P < 0.001). The nationwide vaccination programs were effective, but a substantial proportion of childbearing-age women were still susceptible and need booster vaccination.