Invasive meningococcal infections (IMIs) are notifiable diseases. This article presents the results of a descriptive analysis of data collected for the year 2001. The incidence rate of reported IMIs in mainland France was 1.12 per 100,000 inhabitants in 2001, a rate that has been rising since 1995. The departments with the highest incidence are Southern Corsica, Côtes-d'Armor, and Morbihan. The number of cases and the incidence rate are particularly high among infants under one year of age. Family and community chemoprophylaxis were administered in 88% and 58% of cases, respectively.