In September 2003, the U. S. Department of Agriculture (USDA) Food and Nutrition Service (FNS) contracted with ALTA Systems to conduct a project with the goal of providing a comprehensive overview of the relationship between poverty, program participation and obesity by conducting an in depth literature review; and convening an expert panel. The project goals were to (1) Critically review existing studies and other literature to determine if there is a sound empirical basis for identifying a relationship among poverty, participation in food assistance programs, and overweight/obesity; (2) If the existing research was not found to be conclusive, identify what research approaches, including data sources, would be necessary and feasible to fill the knowledge gaps. FNS provides food assistance benefits through 15 programs. This network of programs plays an important role in providing a nutrition safety net that ensures low-income American families have access to a healthy and nutritious diet. Many low-income individuals are both obese and participants in one or more of FNS' food assistance programs. This project focused on the four largest food assistance programs. Appended are: (1) Literature Review Data Element Definitions; and (2) Bibliography. [Report submitted by ALTA Systems, Inc. and submitted to the Office of Analysis, Nutrition and Evaluation.]