The Secretary issues final regulations for the Assistance to States for Education of Children with Disabilities program under Part B of the Individuals with Disabilities Education Act (IDEA; Part B) and the Early Intervention Program for Infants and Toddlers with Disabilities under Part C of the Act (Part C). These regulations are needed to implement changes made to Part B by the IDEA Amendments of 1997; make other changes to the part B regulations based on relevant, longstanding policy guidance; and revise the requirements on State complaint procedures under both the Part B and Part C programs.