This research project "Modernization, Conservation and Sustainable Development: Engineering in UNESCO since 1945" investigates UNESCO’s engineering activities relating to modernization, heritage conservation and sustainable development since 1945. From an interdisciplinary approach that draws on history of science and technology, heritage studies, and imperial and environmental history, the project analyses the position of engineering in UNESCO thereby shedding light on a critically understudied aspect of post-1945 discourses of modernity and practices of development. The central claim is that close attention should be paid to engineers as influential techno-political experts and that UNESCO provides a privileged path for this because the organization has constituted an enduring transnational platform for debates among technical experts about the potential and pitfalls of global technological modernity. The project is structured under four research headlines: