In this sero-epidemiological study, we investigated humoral immunity to three vaccine-preventable diseases--tetanus, diphtheria and pertussis--among 331 adults (aged 18-60 years) attending vaccination centres for travellers and who had been vaccinated according to national recommendations in France. Serological results showed that the percentage of subjects with antibodies to diphtheria and tetanus decreases with age. Results also confirmed surveillance data on vaccination in France, with 7.6% of the study population (13.4% of those aged 18-29 years) having recently acquired a pertussis infection. These results confirm the importance of following French recommendations for regular boosters for tetanus and diphtheria among adults. They also indicate the need for better implementation of the current recommendations for pertussis-vaccine boosters in adults.