We performed a point prevalence survey for oropharyngeal carriage of common respiratory pathogens in 1404 healthy Turkish children in Istanbul between January 12 and April 25, 2000. Six well-child clinics (WCC) for infants under 2 years of age, 11 day-care centers (DCC) for 3-6 years old, and 7 elementary schools (ES) for 7-10 years old children were randomly selected. Overall carriage rate was 8.5%, 22.8%, 7.0%, 1.3,% and 28.1% for Streptococcus pneumoniae, Haemophilus influenzae, H. influenzae type b (Hib), Moraxella catarrhalis, and any of these organisms, respectively. Carriage rates were significantly higher in DCCs and ESs compared to WCCs. Low-level penicillin resistance (PNSP, MIC 0.05-1.0 ug/ml) was detected in 34 (29%) of 118 pneumococcal isolates, of which 70% fell into serogroups 6, 23, 19, 9, 11, and 3. No high-level penicillin resistance was detected. Serogroups included in heptavalent cojugated pneumococcal vaccine covered 59% of pneumococcal and 82% of PNSP isolates. Multiresistant (>2 antibiotics from different groups) comprised 68% of PNSP isolates. Beta-lactamase activity was detected in 1 (1.1%) of Hib isolates. In-house tobacco exposure was found to be an independent risk factor for carriage of any organism particularly under 2 years of age. Male gender for PNSP carriage, and recent respiratory infection for H. influenzae carriage were also independent risk factors. Recent antibiotic treatment was a reducing factor for carriage of S. pneumoniae, H. influenzae, and any of respiratory pathogens although it was a risk factor for carriage of PNSP. PNSP carriage was more common in private schools compared to government institutions. We conclude that prevention of tobacco exposure, rational antibiotic use, and routine vaccination of infants with Hib and pneumococcal conjugate vaccines should be considered as strategies for prevention of pediatric infections in Turkey