The economic complexity in the age of disruptions: theory and tools

Modern economies are complex adaptive systems, shaped by the continuous interaction of interdependent industries, technologies, and knowledge bases. In such networks, innovation and disruption coexist: shocks rarely remain local but propagate through ripple effect embedded global supply chains, while new forms of value creation emerge from distributed capabilities. Traditional equilibrium-based economic models fail to capture these nonlinear dynamics. This dissertation adopts the lens of economic complexity to investigate how economies evolve under global disruptions and how complexity can inform strategies for resilience and the transition toward circularity. The research addresses two interconnected domains. First, it explores the propagation of systemic shocks across global supply networks through the Gas Energy Branching (GEB) tool, a novel analytical tool developed to map and quantify direct and indirect interdependencies in the global natural gas sector. Using Multi-Regional Input–Output (MRIO) data from EXIOBASE3, the analysis reveals how disruptions originating in the major producers of natural gas, such as the United States or Russia, can generate ripple effects that reach countries and industries not directly engaged in gas trade, revealing structural vulnerabilities within global energy networks. The findings highlight the structural fragility of the global energy system and provide policymakers with a decision-support tool to identify critical nodes, actionable insights for designing diversification and resilience strategies in energy policy and supply chain management. Second, the dissertation extends the tools of economic complexity to the circular economy by introducing the concept of Circular Economy Capabilities (CE capabilities), defined as the skills, knowledge, and organizational routines enabling circular transitions. Two tools are developed: the Country Circular Economy Capability Space and the Circular Economy Capability Proximity Matrix. These tools map the CE capabilities possessed by countries and suggest which CE strategies to adopt based on their capabilities possessed for supporting the effective CE transition. Taken together, the two research components, on systemic disruptions and CE capabilities, offer complementary perspectives on the dual nature of economic complexity. On one hand, complexity can amplify vulnerabilities by transmitting shocks through dense interconnections; on the other, it provides the foundation for adaptation, innovation, and transformation. Recognizing and managing this dual character is essential for understanding how modern economies evolve under pressure and how they can be governed more effectively. The research carries significant managerial, policy, and theoretical implications. From a managerial perspective, it provides tools to identify the most feasible CE strategies across industries, enhancing planning and the effectiveness of circular transitions. The GEB framework helps firms understand global supply chain interdependencies, detect indirect vulnerabilities, and design diversification and resilience strategies. From a policy standpoint, the Circular Economy Capability Space offers a quantitative tool to assess a country’s competitiveness in circular transitions, revealing existing and missing capabilities. This supports targeted investments, capability development, and innovation policy design. In the energy domain, the GEB framework clarifies how shocks spread through global gas networks, informing policies for diversification and energy security, especially relevant amid geopolitical crises such as the Russia–Ukraine conflict. At the theoretical level, the research bridges economic complexity theory, resilience thinking, and circular economy studies, offering an integrated lens to interpret and guide economic transformation. It highlights complexity as both a source of vulnerability and a driver of innovation and opportunity. It argues that complexity is not a problem to be reduced but a resource to be strategically managed, one that underpins resilience, circularity, and sustainable economic transformation in the twenty-first century.