This study uses a unique combination of State panel data and qualitative interviews to examine the economic and policy factors associated with the sharp increase in the number of Food Stamp Program (FSP) participants between 2000 and 2006. This period is particularly interesting because the rise in participation between 2003 and 2006 occurred while the national economy was improving. Higher numbers of participants were associated with higher State unemployment rates and lower State labor force participation rates and minimum wages. The introduction of FSP policies designed to expand eligibility and ease reporting also increased the number of participants. In addition, program outreach efforts were associated with higher caseloads in times of low unemployment. Interviews with State FSP administrators and staff at community-based organizations reinforce the quantitative findings and point to declining local economic conditions and high-quality program outreach as the main sources of caseload growth. The Food Stamp Program was renamed the Supplemental Nutrition Assistance Program (SNAP) in October 2008.