Ethnic identity is theoretically linked to the psychological health of U.S. Latinas/os and has played a preeminent role in the limited literature focused on this group. However, research does not uniformly confirm a positive relationship between ethnic identity and psychological health among U.S. Latinas/os. Emerging work suggests that inconsistencies in the existing literature might be better understood if ethnic identity conceptualizations accounted for context and the developmental period under study. It also has been suggested that the narrow collection of methods and analytical tools used in ethnic identity research prevent a complete understanding of this construct. This article introduces the rationale for consideration of context, incorporation of a life span perspective, and expansion of methodological approaches in the study of U.S. Latina/o ethnic identity, describing the manner in which the four empirical studies in this major contribution illustrate these issues. The practice implications of current findings are summarized after offering suggestions for future research.