Developmental dysplasia of the hip (DDH) is a comprehensive term used to describe an abnormal relationship between the femoral head and the acetabulum. Developmental dysplasia of the hip includes a very wide spectrum of abnormality from a frank dislocation (very unstable) to a stable hip with a slightly shallow acetabulum. As many of these findings may not be present at birth, the term developmental more accurately reflects the biologic features than does the term congenital. Despite the recent increased awareness of DDH and the importance of thorough screening programs, hip dysplasia continues to be a frequently missed diagnosis in pediatrics. Earlier detection and diagnosis of DDH is associated with a much more successful and less invasive outcome.