Other Nations, Other Peoples, a research project of the U.S. Office of Education, studied the degree of ethnocentrism present in elementary, and secondary public school students. The research design was three-way, calling for stratified samples according to county, school and students. The purpose of the study was to determine how ethnocentrism related to age and sex, knowledge of other peoples, educational experiences and geographical and cultural factors. Counties were classified by population size. Fifty counties were selected, of which 25 had populations over 500,000 persons. The smaller counties were stratified according to educational level, income level and region. Two schools were selected from each county and ten students were selected from each school. The resulting formulas for estimation are presented.