McMahon and Watts (2002) found a more achieved ethnic identity to be associated with both less approval of aggressive behavior and less self-reported aggression. This finding was in a sample of 209 predominately African American middle school students from an urban, predominately low-income area. This finding contrasted the finding that higher global self-esteem was associated with more self-reported approval of aggressive behavior (McMahon & Watts). Other research has examined ethnic identity and the externalizing symptom of substance abuse. In a study of 127 11 to 20 year olds, there was a discussion about the association between ethnic identity and high levels of substance abuse. However, this actual statistical finding was not detailed in the article (James, Kim, & Armijo, 2000). There were also differential findings between ethnic groups. The African American adolescents had the highest level of ethnic identity, while there was no significant difference between the Hispanics and European American adolescents (James et al., 2000). The findings contradict the predicted direction of the relationship between ethnic identity and substance abuse. They also demonstrate the need for research that examines ethnic group differences. Conclusions The concept of ethnic identity has only been studied systematically in adolescents over the last 10-15 years. It is clear from this research, that young people are examining the meaning of their membership in ethnic minority groups. Adolescence is the logical period of the lifespan to study aspects of identity formation (Erikson, 1968). Ethnic identity has been consistently associated with positive aspects of psychological functioning in adolescents. Research has demonstrated that ethnic identity can serve as a resiliency factor in certain 'at risk' adolescents, protecting them from adverse outcomes.