An association between headache and sleep disturbances has been reported in previous studies, but there is a lack of research examining this relationship in a community sample of children in order to reveal the magnitude of the problem. Among 32 District Educational Directorates in Istanbul, nine school districts and within each district eight schools were randomly selected. A questionnaire consisting of sociodemographic variables and evaluating headache and sleep disturbances was sent to students' homes to be completed by their parents. The prevalence of headache was 31.4% (95% confidence interval: 29.5-33.4%). Migraine prevalence was 3.3%, whereas nonmigraine headache prevalence was 28.1%. The prevalence of headache was similar between males and females (29.6% vs 33.3%, P > 0.05). The frequency of headache increased with age for both sexes. Snoring, parasomnias, sweating during sleep, and daytime sleepiness were more common among children with migraine compared with nonmigraine and no headache groups. Headaches are common among schoolchildren. Because children with migraine headaches have a high prevalence of sleep disturbances, they should always be evaluated for the presence of sleep problems. (c) 2007 by Elsevier Inc. All rights reserved.