This study sought to produce updated head circumference references in a representative population of Turkish children aged 0 to <84 months. Head circumference measurements are very important in monitoring child growth, to evaluate macrocephaly and microcephaly. Primary sampling units involved family health centers in the city center and suburbs of Kayseri. In total, 2989 children (1479 boys and 1510 girls) were included. Head circumference was measured with a nonelastic tape on a line passing over the glabella and posterior occipital protrusion in children aged 0-2 years lying on a bed, and children aged more than 2 years standing up. We compared the 50th percentile of our cross-sectional data with longitudinal Belgian and American data. The comparison indicated that Turkish head circumference percentiles were similar to, or not much lower than, Belgian and American percentiles. Head circumference percentiles can be used to evaluate children with microcephaly and macrocephaly (+/- 2 standard deviations), and to monitor growth. (c) 2012 Elsevier Inc. All rights reserved.