The Personal Responsibility and Work Opportunities Reconciliation Act of 1996 (PRWORA) fundamentally changed the American welfare system, replacing the Aid to Families with Dependent Children (AFDC) program with the Temporary Assistance for Needy Families (TANF) program. PRWORA deliberately and decisively shifted the authority to shape welfare programs from the federal government to the individual states. California's response to PRWORA was the California Work and Responsibility to Kids (CalWORKs) program-a "work-first" program that provides support services to help recipients move from welfare to work and toward self-sufficiency. To encourage prompt transitions to work and self-sufficiency, CalWORKs, like PRWORA, also imposes life-time limits on the receipt of aid by adults. Finally, CalWORKs devolves much of the responsibility and authority for implementation to California's 58 counties, increasing counties' flexibility and financial accountability in designing their welfare programs. The California Department of Social Services (CDSS)-the state agency responsible for welfare-contracted with RAND for an independent evaluation of CalWORKs to assess both the process and the impact of the legislation, at both the state and county levels.