The present study was prompted by the realization that few of the many reported studies on racial prejudice have dealt specifically with prejudice towards North American Indians. Many studies have investigated the interrelations of Whites and Negroes or Whites and Jews, but not of Whites and Indians. The purpose of this study was to investigate the interracial relationships existing in groups comprised of Indians and Whites. The subjects used in this study were 682 Manitoba public school children and 139 male adult construction workers. The children comprised twenty classrooms drawn from grades 2, 4, 6, 8, and 10. Each grade level was represented by four groups differing in degree of minority concentration as follows: (a) 1 or 2, (b) 3 or 4, (c) from 5 to 7, (d) 8 or more Indian and Metis members in a group. Similarly, the adult level was represented by four groups differing in degree of minority concentration... The results were appraised in two major ways: first, the effect of age on racial self-preference, and second, the effect of minority group concentration on racial self-preference. Cleavage between Whites and Indians was found in both school and adult groups. Young White children exhibited high self-preference which decreased as grade level increased. Young Indian children showed very little self-preference, but self-preference was found to increase gradually as the grade level of the Indian subjects increased... White children showed increasing self-preference as the concentration of Indian children in the groups increased. Although self-preference was absent in Indian children constituting only one or two members of a classroom, it was present when their numbers increased to three or four... Racial self-preference was clearly evidenced at the adult level... Group differences in White self-preference ratios were believed to reflect differences in age, minority group concentration, educational and occupational levels... It was concluded that the self-preference of the White subjects reflected cultural stereotyping, while that of the Indians was due primarily to the direct experience of being rejected by White persons.