PRWORA overhauled the nation’s welfare system by abolishing the previous welfare program, AFDC, and creating the TANF block grant. PRWORA established four broad goals for TANF, which included (1) providing assistance to needy families so that children may be cared for in their own homes or in the homes of relatives; (2) ending dependence of needy parents on government benefits by promoting job preparation, work, and marriage; (3) preventing and reducing the incidence of out-of-wedlock pregnancies; and (4) encouraging the formation and maintenance of two- parent families. Unlike the previous program, TANF gives states great flexibility to design programs that meet these goals. However, while states have flexibility, the programs they design must meet several federal requirements that emphasize the importance of work and the temporary nature of TANF. For example, PRWORA requires that parents receiving assistance engage in work, as defined by the state, after receiving assistance for 24 months, or earlier, at state option. In exercising their option, 28 states require immediate participation in work, and 9 other states require participation in work within 6 months of receiving cash assistance, resulting in great interstate variation in program provisions. Further, despite the programmatic flexibility authorized by TANF, states must meet federal data reporting requirements by submitting quarterly reports that include information from administrative records about those receiving welfare and those terminated from assistance, as well as an annual report, to HHS. The annual report contains information about program characteristics, such as states’ activities used to prevent out-of- wedlock pregnancy. In 1995, we reported that the block grants enacted as part of the Omnibus Budget Reconciliation Act of 1981 (OBRA) carried no uniform federal information requirements. We found that the program information states collected was designed to meet individual states’ needs and that, as a result, it was difficult to aggregate states’ experiences and speak from a national perspective on the block grant activities or their effects. Without uniform information definitions and collection methodologies, it was difficult for the Congress to compare state efforts or draw meaningful conclusions about the relative effectiveness of different strategies. In a second examination of federal block grant programs, we reported that problems in information and reporting under many block grants—the Education Block Grant, the Community Services Block Grant, and the Alcohol, Drug Abuse, and Mental Health Services Block Grant—have limited the Congress’ ability to evaluate them. However, for the TANF Block Grant, the regulations require that states submit the quarterly TANF Data Report and the TANF Financial Report or be subject to statutory penalties. For these reports, HHS provides data reporting specifications including timing, format, and definitions for such data topics as family composition, employment status, and earned and unearned income. These specifications facilitate the use of HHS’ TANF administrative data for welfare reform research by improving the data’s comparability from state to state. Several national surveys and data collected for state and local studies of welfare reform also are potential sources of data for an assessment of TANF. A number of national surveys that collect information about welfare receipt have been used in the past by researchers to analyze welfare reform or have been developed to assess current welfare reform. Four surveys—the Survey of Income and Program Participation (SIPP), the Current Population Survey (CPS), the National Longitudinal Survey of Youth (NLSY), and the Panel Study of Income Dynamics (PSID)—have been used in past research on the AFDC program and the low-income population in general. Both the SIPP and the PSID have updated their questionnaires to include questions that pertain to welfare reform specifically, including questions about the work participation requirements and penalties for not complying with these and other program rules. Moreover, two national surveys are designed specifically to answer questions about welfare reform. The U.S. Census Bureau, at the direction of the Congress, is conducting a longitudinal survey of a nationally representative sample of families, with emphasis on eligibility for and participation in welfare programs, employment, earnings, the incidence of out-of-wedlock births, and adult and child well-being. This survey, the Survey of Program Dynamics, was designed to help researchers understand the impact of welfare reform on the well-being of low-income families and children. Similarly, the Urban Institute has been conducting a multiyear project monitoring program changes and fiscal developments, along with changes in the well-being of children and families. Part of this project includes a nationally representative survey of 50,000 people called the National Survey of America’s Families (NSAF) that is collecting information on the well-being of adults and children as welfare reform is implemented. With the change in the fundamental structure of the nation’s welfare program, there have been several efforts by private research organizations to document the policies states have adopted under TANF. The Center for Law and Social Policy and the Center on Budget and Policy Priorities, in collaboration, have created the State Policy Documentation Project to document policies in all 50 states and the District of Columbia. Available on the Web, the State Policy Documentation Project contains information about state policies contained in statutes, regulations, and caseworker manuals, but it does not describe state practices. In addition, the Urban Institute has developed and made available to the public a database that documents changes in state program rules since 1996. Prior to and since TANF’s implementation, a considerable body of research about the low-income population has been conducted to examine the circumstances of families affected by welfare reform, the effectiveness of welfare reform initiatives, and the implementation of TANF at the state level. HHS has played a major role in laying the foundation for this welfare reform research. During the early 1990s, HHS granted waivers to states that allowed them to test various welfare reform provisions. In return, states were required to evaluate the effectiveness of the waiver provisions by randomly assigning welfare recipients to either participate in the waiver program or not. With the passage of TANF, states were given the option to continue their waiver evaluations as originally designed or modify the evaluation design. Several states opted to continue with their original random assignment design, while others modified their evaluation designs to focus on examining the implementation of the waivers or describe participants’ employment, earnings, and well-being. Because some elements of the waivers granted to states were incorporated into many TANF programs, the waiver evaluations provide useful insights into issues and designs for research about TANF. However, according to HHS, one aspect of waiver policies may mean that some waiver evaluations may not represent TANF requirements completely. TANF established work requirements for all adult recipients, but states could delay adhering to these requirements under their TANF program, in part or whole, if the requirements were inconsistent with state waiver policies. Under the Job Opportunities and Basic Skills Training (JOBS) program, work requirements were mandatory for a work-ready or able-bodied population, excluding a number of subgroups such as those caring for young children and the disabled. For the most part, states that continued the original random assignment design maintained some or all of the JOBS exemptions from work requirements and applied these exemptions in determining who was subject to time-limited assistance. Consequently, while these states’ waivers may incorporate other work policies prescribed under TANF, these policies would not be expected to affect the exempt population. In contrast, in states that do not claim JOBS exemptions from work requirements, all adults are subject to work requirements and time limits on assistance. Thus, while testing TANF-like policies, evaluations that continued the random assignment design may not fully reflect the experience, outcomes, or impacts of fully implemented TANF requirements. In addition to the waiver evaluations, HHS, as well as private foundations, has provided funding for demonstration programs across the country. The demonstration programs are pilot projects designed to measure the effects of a particular strategy, rather than an entire program, on welfare recipients or those eligible to receive welfare. Many of these demonstration programs were intended to increase employment, decrease out-of-wedlock pregnancy, or promote marriage. For example, in the late 1980s, several demonstration programs aimed at decreasing teen pregnancy among welfare recipients were developed. One program, the New Chance Demonstration, randomly assigned teen mothers receiving welfare to participate in a program that offered education or training classes and other support services and then compared the accomplishments of these teen mothers with those of teen mothers who did not participate in the program. Given states’ greater responsibility for welfare programs under PRWORA and the larger number of people leaving the welfare rolls, there has been general interest among program administrators and state and local policymakers about the condition of those who are no longer receiving TANF, otherwise known as “leavers.” In response to this concern, a growing body of research about leavers has been initiated at both the state and federal levels. Generally, researchers have found that once low-income families leave welfare, they become hard to keep track of. Moreover, we previously reported that studies of former TANF recipients’ status differ in important ways, including geographic scope, the time period covered, and the categories of families studied, which limits the comparability of the data across states. In order to facilitate cross-state study comparisons, the Office of the Assistant Secretary for Planning and Evaluation (ASPE) within HHS has issued guidance to states and the research community on developing comparable measures for commonly reported outcomes and defined these outcomes. In fiscal year 1998, ASPE awarded approximately $2.9 million in grants to 10 states and three large counties to study leavers, followed by additional grants in fiscal years 1999 and 2000. ASPE also has encouraged the researchers to use comparable measures. Research is also being conducted to examine the effects of welfare reform in metropolitan areas or neighborhoods.