This report presents findings from a study of factors affecting the decision by families that leave the Temporary Assistance for Needy Families (TANF) program to participate in the Food Stamp Program (FSP). Linked Illinois state-level administrative data are combined with Census data and data from the Illinois Families Study survey to evaluate the decision of TANF leavers to participate in FSP. Results indicate that in Chicago, neighborhood characteristics and knowledge of FSP eligibility at the district office level are important factors in understanding the FSP participation decisions of TANF leavers even after individual or family-level demographic characteristics are taken into account. This evidence suggests that the density of social networks among the food-stamp-eligible population in the district office areas may mediate the effects of office outreach and communication strategies.