This article aims to conduct a case study on urban planning models drawn by social scientists in 1970s Romania. It looks at the trans-national channels of knowledge circulation and reconstructs specialists’ role in creating new bridges of cooperation between the first and second world. It also analyzes the gradual re-signification of these ideas locally as part of the socialist state development project. More precisely, it wants to answer three intertwined questions: To what extent did the trans-nationalization of knowledge in the late 1960s determine a particular approach to urban planning in Romania? What does this tell us about local professional practices’ autonomy? Which was the international relevance of Romanian social sciences’ practice? The article contributes to an emerging scholarship on the genealogy of these ideas by placing the transnational debates of the late 1960s and early 1970s consumed under the umbrella of various international organizations, such as the ISA and the UN, in conversation with an intellectual tradition dating back to the interwar period.