After the Second World War, in a paradoxical era of renewed internationalism and growing geopolitical tensions, the social sciences expanded as never before, both quantitatively and geographically. An important key promoter behind this development was UNESCO, whose newly established Department of Social Sciences worked in various ways for the internationalization of the social sciences. The subject of my book is to investigate these activities, with special focus on the half-decade 1950-1955 during the directorship of Alva Myrdal. More specifically, it analyzes Myrdal's and the department's visions and practices in an organizational and geopolitical context. What type of organization was UNESCO? How can Myrdal's internationalism best be characterized? How was the work conducted in practice? And how can this be understood in relation to contemporary geopolitical tensions? The book offers the first systematic study of Myrdal's endeavors at UNESCO and thus makes an important contribution to the knowledge about Myrdal’s international engagements and UNESCO's Department of Social Sciences. It also contributes to international research on the development of the social sciences during the Cold War and hence also, indirectly, to our understanding of the social sciences today. The application is intended for one year’s full-time research for the completion of a full-length book manuscript and includes two months research in residence at the University of Toronto.