This policy brief begins with a broad overview of what the science of early childhood development tells us about the first three years of life. It then outlines the actions that need to be taken during the reauthorization of the Individuals with Disabilities Education Act (IDEA) to increase the likelihood that policy decisions are guided by state of the art knowledge about early human development and not by ideologically driven advocacy. The following four policy recommendations are discussed: (1) permanently reauthorize Part C of IDEA; (2) provide sufficient funding to identify and serve all infants and toddlers with developmental disabilities or delays; (3) enhance early identification (child find) of infants and toddlers with disabilities; and (4) improve the overall quality of services. A description and brief history of Part C of IDEA is given. Includes 9 references. (Author/SG)