The Survey of Income and Program Participation (SIPP) offers important new opportunities for improved policy research and analysis. Validating the new data against existing administrative data sources is an important first step towards capitalizing on these opportunities. This paper compares the distribution of Food Stamp Program participants on selected demographic and income variables obtained from SIPP and from a survey of administrative case records. In general, the two data sources generate similar results. There is, however, a significant improvement in the match when SIPP household units are redefined to correspond more closely to food stamp assistance units.