This chapter addresses a two-part question about US racial boundaries and the place of the Latino immigrant population therein. First, how do Latinos see themselves fitting into the US racial order; that is, how do Latino immigrants define themselves when confronted with the US system of racial classification. Second, on the flip side, how are Latino immigrants influenced by the existing system of racial stratification in the United States. The chapter focuses on Latino immigrants' responses to federally mandated racial identification choices by predicting racial identification in three categories: white, nonwhite, and refused to answer. It explores the other side of immigrants' perceptions of racial categories: whether Latinos are subject to effects of a racial stratification system based on phenotype. Light-skinned Latinos and those less integrated into the United States are likely to continue to test the flexibility of the white racial boundary.