This report examines factors related to differences in the percentages of county population participating in the Food Stamp Program among U.S. counties in May 1970. Factors associated with higher food stamp participation rates were higher unemployment and welfare program participation rates, greater proportion of households with low Income, a higher percentage of population 17 years or younger, and longer participation of the county in the Food Stamp Program. Factors associated with lower food stamp participation rates included greater labor force participation and a higher percentage of population 65 and older. The presence of a direct food distribution program prior to the county’s participation in the Food Stamp Program had little discernible effect. Despite higher participation rates in counties with higher percentages of minorities and the more rural of the nonmetropolltan counties, when other factors affecting participation rates are held constant--mainly percentage in poverty--the analysis suggests that participation in these counties was not as high as in counties with smaller percentages of minorities or in more urban counties.