This article reviews recent changes in public assistance in the US that influence fertility family formation and family maintenance behaviors. It identifies lessons learned that might guide state reforms under the Temporary Assistance for Needy Families (TANF) Act. TANF was passed in 1996 with the Work Opportunity Reconciliation Act (PRWORA). In 1996 reforms were motivated by the view that AFDC promoted irresponsible and/or self-destructive behavior. By 1996 42 states had applied for waivers of federal welfare regulations. Requests pertained to eligibility of 2-parent families (34 states); welfare participation requirements (40 states); benefits and services (37 states); and income and asset disregards (37 states). Public attention has focused on the family cap and the unemployed parent (UP). New Jersey was the first to adopt a family cap (1992) which restricted additional assistance for additional children born to welfare recipients. Charts identify key features for the 21 states with family cap provisions and provisions for the 33 states with UP rule waivers. The author reviews the research literature underlying PRWORA and discusses the evaluation of the New Jersey program. The authors substantiate why state evaluations are unlikely to differentiate causal links between selected welfare reforms and family outcomes. The authors suggest other research focuses that would better serve policy needs: predicting behavior responses to welfare policies contextual and ethnographic analysis and targeted experimental evaluations. Unfortunately little understanding was gleaned about how pre-1996 reforms affected family behavior.