The nuclear sector finds itself at a critical juncture, in part because recent large nuclear power plant projects in Europe and the United States have suffered from what some scholars have called megaproject “pathologies,” that is, the chronic failure of large, complex infrastructure projects to fulfill the “iron triangle” criteria of project performance: cost, timetable, and predefined project prescriptions. To explore the framings of such problems within the nuclear community, this paper analyzes the ways in which 19 experts at the Nuclear Energy Agency (NEA), under the Organisation for Economic Co-operation and Development (OECD) diagnose such problems and their underlying causes. The analysis draws on framing theory and on the scholarship on megaprojects, with semistructured interviews providing the empirical material. The identified four frames highlight as key explanations for pathologies the “vicious circle” of lacking investment, erosion of skills, and construction problems; “bureaucratization and contractualization”; “broken markets”; and “complexity and nuclear-sector exceptionality.” Two overarching metaframes attribute the ultimate reasons to factors outside the projects and the nuclear community, notably to the lack of political leadership and the inability of the modern Western society to identify and pursue its own interest. The NEA frames bear significant resemblance to the alternative megaproject literature, which calls into question the very notion of pathology; stresses the complex, open systems character of megaprojects; and calls for flexibility and adaptability to better align megaprojects with their evolving context. However, the vital need to ensure and maintain an appropriate fit between nuclear-sector megaprojects and their ever-evolving environment deserves greater attention. Toward this end, introduction of OECD-style country peer reviews could constitute an opportunity toward collective “frame reflection,” in interaction with communities offering competing framings of the pathologies. Further research would be welcome on the role of the NEA in framing processes within the nuclear community and on the relationships between megaprojects and modernity in this high-risk industry.