In addition to biologic mechanisms, cultural factors are important determinants of sleep practices and behaviors in infants, children, and adolescents and influence both the type and frequency of sleep problems found in the pediatric population. This article discusses some of the key sleep practices most influenced by cultural practices and beliefs: cosleeping, bedtime rituals, the sleeping environment, napping, and parental expectations regarding sleep in children. The importance of clinical and educational cross-cultural collaboration and the need for future research that uses culturally sensitive and comparable methodologies to explore cultural differences and similarities are emphasized.