Early identification of children with developmental delays is important in the primary care setting. The pediatrician is the best-informed professional with whom many families have contact during the first 5 years of a child's life. Parents look to the pediatrician to be the expert not only on childhood illnesses but also on development. Early intervention services for children from birth to 3 years of age and early childhood education services for children 3 to 5 years of age are widely available for children with developmental delays or disabilities in the United States. Developmental screening instruments have improved over the years, and instruments that are accurate and easy to use in an office setting are now available to the pediatrician. This statement provides recommendations for screening infants and young children and intervening with families to identify developmental delays and disabilities.