Drs. Vera Joanna Burton and Jacqueline Weissman of the Kennedy Krieger Institute and the Johns Hopkins University School of Medicine explain methods for the identification and evaluation of delayed development in children. This clinical summary reviews core principles of development in children. Evaluation methods aimed at the identification of developmental problems in primary care and specialty care will be discussed. The specialty medical evaluation and management of children with identified developmental disorders will be reviewed, including recent recommendations about genetic testing.