Streptococcus pneumoniae (Sp) colonizes the upper respiratory tract within the first few months of life and is part of the normal flora of the nasopharynx. It is also responsible for invasive infections, pneumonia, and particularly severe cases of acute otitis media in young children. Since March 2002, and again in March 2004, the vaccination schedule has recommended the use of the heptavalent pneumococcal conjugate vaccine (Prevenar®). It protects children under 2 years of age in whom the polysaccharide vaccine (Pneumo 23®) is not immunogenic. It is specifically indicated for children at high risk of pneumococcal infection due to an underlying medical condition or due to close contact with young children (siblings, daycare, nursery). New Caledonia constitutes a unique epidemiological entity due to its island geography and its multi-ethnic population of 220,000 inhabitants. Pneumococcus is the leading cause of bacterial meningitis there. With 4,400 births and 5 cases of meningitis among children under 5 years of age each year, the incidence of pneumococcal meningitis is 22.7 per 100,000 inhabitants—six times higher than that observed in mainland France. Vaccination could therefore be recommended provided that the concordance between the serotypes present in the region and the vaccine valences is verified beforehand. Thus, since colonization generally precedes infection, it seemed worthwhile to identify the serotypes present in nasopharyngeal carriage among New Caledonian children—reflecting circulating and potentially pathogenic strains—to complement a previous study of serotypes isolated from patients (1999–2001). (R.A.)