The purposes of this study were to determine: (1) if differences existed in the self-concept among Negro, Anglo, and Spanish American students; and (2) the extent to which these differences were influenced by ethnic group membership, socioeconomic position, sex, or the interaction among these variables. This study was carried out in a New Mexico public school system and involved students from two junior high schools during the academic year 1968-69. The total group sample was comprised of all ninth grade students in these two schools for which four data indices were available: (1) scores on the "Tennessee Self Concept Scale" (TSCS), (2) scores on the "Hollinghead Two Factor Index of Social Position" (ISP), (3) classification as to ethnic group membership, and (4) sex. The final sample included 607 subjects. The subjects were assigned to categories on the basis of their sex, ethnicity, and social class position. The scores which follow, taken from the TSCS, were separately subjected to a three way classification of variance: (1) Total Positive Score, (2) Identify, (3) Self-Satisfaction, (4) Behavior, (5) Physical Self, (6) Moral-Ethnical Self, (7) Personal Self, (8) Family Self, (9) Social Self, (10) Variability Score, (11) Distribution Score, (12) Total Conflict Score, (13) Self-Criticism Score, and (14) Defense Positive Score. (Author/JM)