Recent research in cultural diversity has concentrated on the complexity of ethnic and racial identity. This study measures the bicultural and global-human identities among first- and second-generation, Mexican-American adolescents. The participants, (84 male, 93 female) from Los Angeles high schools, had both parents of Mexican descent (60 of the adolescents were born in Mexico and 117 were born in the United States). The study incorporated existing instruments and dealt with affective rather than behavioral aspects of social identity. Factor analysis yielded three meaningful independent identities: (1) Mexican (Latino); (2) Mainstream (American); and (3) Global-human. Gender comparisons yielded no differences in American, Latino, and Global-human identities, nor in acculturation, ethnic pride, and educational aspiration. However, boys did score significantly higher than girls on self-esteem while girls scored higher on the importance of educational achievement. The author used Latino and American identity measures to identify J. Berry's four modes of acculturation: separated, assimilated, marginalized, and bicultural. No differences appeared in the acculturation groups in self-esteem and academic aspiration, although the bicultural group tended to score higher on global-human identity. Generational comparisons revealed that first and second generation participants scored equally high on ethnic identity as compared to American identity. (Contains 44 references.) (RJM)