Despite the availability for more than two decades of an effective vaccine against measles, major outbreaks in Israel have occurred in recent years and can be expected to occur in the future because large numbers of children have never been vaccinated against the disease. The main public health challenge should be to locate and vaccinate those children aged 16 months to 5 years who have never been vaccinated, since it is among these children that incidence, complications and mortality are highest. Although a second routine measles vaccination to schoolchildren will decrease the number of susceptibles, this new program feature will not eliminate outbreaks and must not be allowed to divert attention from the essential target group.