Economically disadvantaged (ECD) students come to classrooms performing below grade level, particularly in reading. The purpose of this qualitative case study was to examine master educators' identities and practices that contribute to success in literacy development with ECD students. The performance of ECD students compared to more affluent students on state standardized tests shows enormous disparity. An effective teacher is vital to student success. Qualitative data were collected through semi-structured interviews and classroom observations with six master teachers. Findings regarding teachers' identity impact on student achievement provide evidence organized by Mockler's identity domains of personal experience, professional experience, and political influence. Observations revealed commonalities among master teachers, including foci on academic vocabulary and small group instruction. Interviews and observations of master teachers showed a reverence for classroom organization, knowledge of content, teacher-student interactions, and the ability to not dwell on barriers to learning, thereby supporting student literacy development. Data regarding characteristics and qualities of master teachers emerged, providing a potential link between teacher identity and instructional literacy practices that are effective in teaching ECD students. Study findings support teachers and school districts who are struggling to meet the demands of high stakes testing. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]