Rapid population growth, significant population movements, and difficulties in accessing healthcare in French Guiana make it essential to regularly assess vaccination coverage and continuously adapt vaccination strategies. In coastal municipalities, a cluster-stratified survey, based on the method established by the WHO, was conducted from October 9 to 20, 2000, among children aged 2–3, 7–8, and 12–15 years for all antigens in the vaccination schedule, and among those over 15 years of age for yellow fever. In inland municipalities where population sizes were too small to justify this approach, a comprehensive school-based assessment was conducted among children aged 7 to 8 in the following weeks. The results were systematically compared with those of the last survey conducted in 1991 to measure changes in vaccination coverage. In the coastal zone, an improvement was observed only for vaccination coverage at 24 months with the yellow fever vaccine, which rose from 34% to 61% over 10 years... Vaccination coverage at 24 months against measles, mumps, and rubella has remained below 70% for the past 10 years. Vaccination with the 4-dose DTP-Polio series remains low, with only 1 in 2 children properly vaccinated at 24 months and 61% at 12 years. Early BCG vaccination, which is steadily declining, is severely insufficient, with only 10% of children vaccinated before 1 month of age. The results found throughout the Maroni River region are worse for all vaccinations. Vaccination coverage at 24 months ranges from 45% to 72% for BCG, from 21% to 33% for 4 doses of pertussis, from 46% to 61% for measles, and from 3% to 38% for yellow fever. In coastal municipalities, a significant effort must be made by all partners involved in childhood vaccination (vaccination centers, maternal and child health centers, private practitioners, hospitals, and school health services), particularly for vaccinations against pertussis, measles, rubella, and mumps. In inland municipalities, catch-up campaigns should be organized and routine vaccination activities strengthened. (R.A.)