During 2002, there were disputes about most aspects of the participation rate structure for Temporary Assistance for Needy Families. The Administration put forward, and the House adopted, a proposal to raise TANF participation rates to 70 percent over 5 years, require families to be in selected activities for 40 hours per week to be fully countable, and to restrict activities that counted toward the first 24 hours a week of participation. This document examines what available data say about the extent and nature of TANF participation in 2001 and how current TANF participation differs from what is required under the Administration's approach. Findings include: the national average participation rate in 2001 was 34.4 percent, with significant variation between states; actual participation levels were clearly higher, though due to limits in federal participation reporting it is impossible to precisely state the share of TANF adults involved in work-related activities; the most common activity counting toward federal participation rates was unsubsidized employment; participation in education and training remains low, but has increased modestly in recent years; and most states would need to make large changes in program design in order to meet the Administration's participation requirements. An appendix summarizes current law and the Administration's proposal. (SM)