This dissertation explores the conceptualization of education equity as manifested in the work of the UNESCO International Institute for Educational Planning (IIEP), a UNESCO institute with a technical mandate on research, training, and technical cooperation in educational planning and management. The study raises the questions of how UNESCO-IIEP approaches, addresses, and conceptualizes equity through its organizational life and work, and connects this conceptualization to the organizational structures, goals, technology, environments of the institute. It analyzes these connections using constructs from organizational theory that enable understanding and evaluation of IIEP's role in global education development and its work on equity. The study approaches education equity with a conceptual framework of equity and justice articulated by John Rawls and Amartya Sen that distinguishes between arrangement-focused and realization-focused views of justice. The methodological framework builds upon constructs in organizational theory with an ethnographic orientation, drawing on observation, interviews, and document analyses within my five months at the institute. The contextual framework situates the role and work of UNESCO and IIEP within global educational governance. The findings characterize equity with different layers of complexities, highlighting its many dimensions and dilemmas as conveyed through the organizational life and work of IIEP. These dimensions and dilemmas are connected to the organizational features of the institute, which include its strong and tightly coupled technical core, its clear mandate and well-developed technology, its informal and collegial social atmosphere, and the complex relationships and interactions it has with actors in its environments. These features intersect and interact within the complex dynamics of organizational legitimacy and performance, shaping and defining the concept of equity as IIEP establishes itself and operates within the space of global educational governance. These dynamics inform organizational learning and are the basis on which IIEP situate and evaluate its role and its work on equity in the global context. The dissertation makes several contributions to the study of global educational equity. Conceptually, it brings new insights into the discussion around education equity and how actors in global education address equity. Equity in global education is often more complex than the singular, universal concept reflected in the global discourse, and addressing equity issues often calls for an arrangement-focused rather than an institution-focused view of justice. Methodologically, it approaches and brings organizational theory into the qualitative study of organizations, combining the theoretical rigor of the former with the data richness of the latter. Contextually, it presents a case for studying the conceptualization of equity in international organizations and the impact such a conceptualization may have. The role of IIEP as a prominent technical organization and its status within the UN/ESCO network allow its conceptualization of equity to both inherit from and add to the understanding and characterization of the concept in global educational governance. This work adds to the growing volume of studies on international and intergovernmental organizations in education, and, with its ethnographic orientation, highlights both the consequence and the complexity that characterize their work. [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.]