The U.S. Census Bureau began using monetary incentives in the Survey of Income and Program Participation (SIPP) in an attempt to combat the steadily increasing nonresponse that occurred over the life of the sample. Becuase the SIPP provides national estimates of sources, amounts, and determinants of income for households, families, and individuals, it is the primary source of data for evaluating the effects of welfare reform. Therefore, it is imperative to achieve a high response rate so that policy makers have an accurate picture of the economic situation of all Americans. The literature concludes that the positive effects of incentives in mail surveys also hold in surveys conducted by interview in person or by telephone as well as for fresh respondents, panel respondents, and nonrespondents (Singer et al. 1999). Multiple experiments were embedded in the 1996 and 2001 Panels. These experiments tested the differentail effects of: $0, $10, or $20 unconditional incentives using both paper vouchers and plastic debit cards; $20 'booster' incentives for poverty household; and $0, $20, or $40 conditional incentives for previous wave nonrespondents. In this presentation, we provide a historical context of the 1996 Panel experiments; present the results (i.e., response rates, hard refusal rates, receipt of multiple incentives, and respondent reaction to receiving an incentive) of the 2001 Panel experiments which represent the last opportunity to benchmark response rates using a control group; and, conclude with the preliminary results of the 2004 Panel in which the use of incentives became standard practice.