Vertebral osteomyelitis (VO) is a rare event. To estimate the incidence of VO in France for 2002-2003, national hospital-discharge data were used. Hospital stays were categorized as definite, probable or possible VO. Unique patient identification numbers allowed the investigators to link patients with multiple hospital stays and to analyse data for individual patients. A sample of medical records was reviewed to assess the specificity of the VO case definition. In 2002-2003, 1977 and 2036 hospital stays corresponding to 1422 and 1425 patients (median age 59 years, male:female ratio 1.5) were classified as definite (64%), probable (24%) and possible (12%) VO. The overall incidence of VO was 2.4/100,000. Incidence increased with age: 0.3/100,000 (70 years). The main infectious agents reported were Staphylococcus spp. (38%) and Mycobacterium tuberculosis (31%). The most frequent comorbidities were septicaemia (27%) and endocarditis (9%). Three percent of patients died. A review of 90 medical records confirmed the diagnosis of VO in 94% of cases. Using a hospital database and a specific case definition, nationwide surveillance of VO is possible.