International Baccalaureate (IB), a highly rigorous academic and college preparatory program, has sometimes been implemented to turn around otherwise struggling school systems. Little is known about the impact on school culture from the implementation of IB in a low-achieving, high poverty school through the lens of critical theory and leader-member exchange theory. The purpose of this study is to gain teacher and student perspectives on the culture of a high school twenty years after the introduction of IB. The research questions that guided this study were as follows: Based on staff and student perceptions, what is the current culture at Central High School? What is the role of International Baccalaureate in that culture? Findings indicated that the culture of this high school was diverse, historic, superficially unified, and deeply divided. Findings further indicated that IB both encouraged diversity within the school, as well as facilitated division. Implications from this research state Central will continue to survive, and perhaps even grow, as a diverse and historic educational institution, however, the approach used towards cultural division will continue to perpetuate social, educational, and economic disparities within that school.