In the United States, early childhood inclusion dates back to the civil rights movement with the 1954 case of Brown v. The Board of Education, an issue of segregation by race in schools and followed by the Americans for Disability Act (ADA). A Free Appropriate Education (FAPE) in the Least Restrictive Environment (LRE), from Individuals with Disabilities Education Act (IDEA) has influenced inclusive practices. Both the IDEA and the No Child Left Behind (NCLB) provide language supporting early childhood inclusion, but the implementation of inclusion has been uneven. Many factors influence practice, including changes overtime in the interpretation of existing laws, definitions of what is inclusion and research outcomes of inclusive practices. Local infrastructure for serving young children, funding, qualified personnel, motivated leadership and teachers, and informed parents are also factors impeding or facilitating early childhood inclusion. The complexity involved suggests a dynamic process with uncertain pathways from policy to practice.