Despite the series of documents by the sacred ecumenical council and replete research enumerating the two-dimensional focus of Catholic schools: faith and academics and its collaborative nature, Nigerian (southeast) Catholic primary and secondary schools are continually experiencing activities of disharmony between Catholic identity and students' academic achievements. To better understand the nature of disharmony and its causes from the perspectives of leaders, teachers, and parents, this study examines the major challenges that face the representation and teaching of Catholic identity and the students' academic achievement in the Catholic schools of southeastern Nigeria. While the purpose is critical to the student's overall success, the study draws on the Culturally Responsive Teaching (CRT) theory of Geneva Gay. The theory provides the basis for the argument that Catholic identity is the culture of the school and the students. As such, for the overall success of the students, their learning should be situated within their Catholic cultural background and experiences. Through a convergent mixed-method research design, quantitative data were collected through surveys from administrators, teachers, and parents, while qualitative data were collected through one-on-one interviews with administrators and parents and a focus group with teachers. Findings suggest a tension between Catholic identity and academic achievement caused by the use of a common curriculum and common examination, unqualified educators, examination malpractice, lack of complete knowledge on what constitutes Catholic identity, a decline of Catholic values, a focus on academics, tension between maintaining Catholic identity and increase in enrollment, pressure from parents, and lack of parental engagements. Primarily, the situation hovers around the premise of leadership; as such, this study recommends the roles of leaders in their practical approaches to eliminate the tension between Catholic identity and academic achievement and present relevant implications for policy and practice. Findings from this study reveal the importance of recruiting and hiring educators who are qualified and committed to promoting a culturally responsive Catholic education. Future research should include the voices of the students to reveal additional insights into the nature of Catholic identity in Southeast Nigeria. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]