Two years after receiving live rubella virus vaccine, 625 school children were retested to determine the persistence of vaccine-induced antibody. There was no significant change in antibody between seven weeks and two years after vaccination in 307 of 313 Cendehill strain vaccinees and 282 of 299 high passaged virus (HPV)-77-dog kidney (DK)-12 strain vaccinees. Five Cendehill and 6 HPV-77-DK-12 vaccinees experienced a significant decrease in antibody titer, and one Cendehill and 11 HPV-77-DK-12 vaccinees experienced a significant increase in titer. Thirteen children were revaccinated; one had a significant boost in antibody titer. Among a control group of susceptible adolescent girls not vaccinated, 86 of 93 remained susceptible. Two control girls had clinical and five had subclinical rubella. Medical and laboratory surveillance revealed little rubella in the school system during the two-year period.