A serosurvey of 2,456 high-risk employees of the Los Angeles County-University of Southern California Medical Center showed that 345 (14%) were susceptible to rubella. Of 197 seronegative personnel followed up for participation in a vaccination program, 105 (53.3%) were vaccinated. However, only one of the 11 known susceptible obstetrician-gynecologists was vaccinated. Thirty-eight seronegative employees who were vaccinated with RA 27/3 rubella vaccine were queried four to six weeks after vaccination and compared with 32 unvaccinated seropositive control subjects. Although the reaction rate was 50% among vaccinees and 3% among control subjects, each vaccinee lost only an average of 0.2 workdays compared with 0.1 workdays for control subjects. The high rate of susceptibility to rubella among hospital employees supports the need for screening. Although vaccine reactions are common, they are generally mild. Means must be found to ensure greater employee acceptance of vaccine.