Since early 2010, a measles outbreak has been observed in the French armed forces. The objective is to present the results of epidemiological surveillance of measles in the armed forces between 1992 and 2010 and to describe this increase in incidence. The criteria for reporting measles were based on those used for mandatory national reporting. Data concerning active-duty military personnel were reported by all military unit physicians using an anonymous data collection form. Between 1992 and July 2010, 689 cases of measles were reported. Since 2002, the average incidence rate was 1 case per 100,000 person-years. A significant increase was observed in 2010 (13.9 cases per 100,000 in 2010 versus 1.8 in 2009). The 28 cases reported in 2010 were distributed across 6 clusters and 3 isolated cases. Vaccination status information was available for 20 cases, of which 6 had been vaccinated (30.0%). The resurgence of the measles epidemic observed in 2010 within the French armed forces is consistent with that observed at the national and European levels, likely a consequence of insufficient vaccination coverage. Military personnel may constitute a relatively exposed population given their communal living arrangements. (R.A.)