The "new federalism" paradigm offers an explanation why the federal government has devolved much of its administration of the Temporary Assistance for Needy Families (TANF, formerly AFDC) and Medicaid (through managed care) programs. A review of child and family outcomes data resulting from these devolutionary changes in TANF and Medicaid indicates that these devolutionary changes generally appear to have decreased access to medical coverage, decreased well-being out-comes, decreased cognitive development, increased behavioral and emotional difficulties, and increased the incidence of poor health for children and families. If the "new federalism" paradigm is extended to the Head Start program by block granting it to the states, children and their families served by Head Start are in potential jeopardy of suffering similar fates. This strong possibility should make policy makers very cautious about devolving or block granting the Head Start program to the states. (Contains 2 tables and 23 footnotes.)