When in the late 1960s, a radical pan-Scandinavian design movement initiated a full-blown attack on the ‘architectural damage’ wrought by Modernist welfare architects, their localized grassroot-activism appeared far removed from formal machinations of Cold War geopolitics. Yet, the influential environmental design discourse they helped promulgate, was inextricably tied to U.S. government-sponsored transdisciplinary experiments in industrial design, engineering and social science that had sprung up in institutes across the U.S., ranging from MIT to Purdue University. As the influential post-development anthropologist Arturo Escobar has argued, design acted as a crucial (yet routinely overlooked) mechanism of Cold War development policy and its discontents. Based on original archival research, this talk explores how a distinct genre of transdisciplinary design became instrumentalized in U.S. development agendas across the Global South, examining its residual legacy in contemporary user-based corporate design practice.