World.OS – Rethinking International Cooperation in a Multiplex World explores how international cooperation must evolve in a world where power is no longer concentrated, but distributed. As geopolitical tensions rise and technological competition reshapes global dynamics, traditional models of cooperation—based on aid, asymmetry, and static institutions—are reaching their limits. At the same time, countries across the world—often referred to as middle powers—are facing a shared challenge: how to build resilience, technological sovereignty, and political agency in a fragmented world?