This in-depth case study of classroom interaction illuminated how a white female teacher and African American students used talk to build positive authority relationships across their racial difference. Racial difference in classrooms can engender cultural misunderstandings between teachers and students around behavior, communication, and learning styles. Focusing on Black/White relationships as a particular configuration of racial difference, this study demonstrated how a white teacher's authority was constructed in culturally responsive and relevant ways through her engagement in and legitimization of Signifyin(g), a culturally-specific, African American discourse practice. Ethnographic discourse analysis made visible the process by which this teacher used authority established through Signifyin(g) for an array of educational purposes--to discipline students and manage the classroom while minimizing conflict; position students as the co-producers of knowledge; construct participation structures that afforded students access to and engagement in learning; and build cross-racial political alliances. Conceiving of authority as a process, product, and relationship highlighted the discursive moves the teacher made to accumulate cultural capital and build connections with students over time and from one moment to the next. Contextualized by the taken-for-granted, everyday life of the classroom, multiple forms of authority practiced by the teacher and students were made vivid by analyzing episodes of classroom interaction that featured Signifyin(g). Results enabled an articulation of culturally responsive authority, constituted through discourse and the legitimization of students' culturally-based discourse practice. Practicing culturally responsive authority requires effective use of classroom discourse to accomplish educational goals coupled with a deep understanding of language variety. The centrality of classroom discourse in building cross-racial authority relationships emphasized the need for prospective teachers to study representations of classroom interaction, such as portrayed in this dissertation, and reflect on how they use language in the classroom. Pointing out the particular implications for white teachers, this dissertation calls for teacher preparation to foreground teachers' use of language and incorporate pedagogical approaches that cultivate cross-cultural empathy, awareness of social inequalities, and a white identity that serves as a source of legitimacy in the classroom. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]