After seven years without indigenous transmission of measles in Bulgaria, an increasing number of cases have been reported since 15 April 2009. By 19 June, the total number of notifications reached 84. To date, 64 were confirmed as measles cases and 15 cases, for whom laboratory results are pending, have been classified as probable. The present measles outbreak affects mostly the Roma population living in the north-eastern part of the country. The most affected age groups are young children below 1 year of age and children 1 to 9 years of age. An immunisation campaign was started in the affected administrative regions, targeting all persons from 13 months to 30 years of age who had not received the complete two-dose MMR vaccination.