This article revisits the methodological foundations of Elinor Ostrom’s institutionalism by examining the role of ‘complexity’ in her work and the conceptual influence of Herbert A. Simon. While Simon was not Ostrom’s most frequently cited reference, his thought – particularly as articulated in The Sciences of the Artificial – exerted a formative and enduring influence on her analytical framework. Drawing on Ostrom’s later writings, in which she offers a retrospective account of her intellectual trajectory, we show how Simon’s systems-engineering perspective provides a coherent framework for understanding her approach to institutional complexity, despite notable differences in their respective research objects and theoretical priorities. For Ostrom, institutions evolve incrementally as ‘boundedly’ rational individuals attempt to resolve collective problems through successive modifications of rule structures within complex social systems. In contrast to top-down optimisation models, her work emphasises adaptive responses and practical problem-solving. Interpreting Ostrom’s methodology through a Simonian lens not only deepens our understanding of her contribution to institutional economics but also illustrates the value of interdisciplinary approaches informed by complexity theory for the field.

This study sheds light on the diffusion of knowledge production as an institutional norm among central, development, and investment banks. It builds on an original database of 24,435 peer-reviewed scientific items published by a pool of 237 central banks, development banks, and investment banks from 1966 to 2023. The focus is on their interactive dynamics, analysed through a two-fold approach: Granger-Causality analysis for linear relationships and a multivariate Markov chain approach for non-linear interactions. Central banks emerge as leaders in scientific production, influencing development and investment banks. Results lead to further questions about inter-institutional agenda-setting, such as how central banks shape research priorities, the extent to which their intellectual leadership impacts others’ priorities, and the mechanisms through which institutional norms are diffused and reinforced within the global financial and policymaking landscape.

Our study investigates the impact of successful violent and non-violent revolutions on post-revolutionary institutions concerning women. Leveraging the Nonviolent and Violent Campaigns and Outcomes data on successful revolutions and the Varieties of Democracy dataset for gender-specific metrics, we employ fixed-effect difference-in-differences and Callaway Sant’Anna. Our results show positive effects from both treatments. Non-violent revolutions with regime change intentions have a more consistent positive impact on women’s empowerment indices than violent revolutions, while revolutions without regime change intentions show mixed or limited effects across both violent and non-violent cases.

Why does collaboration among competitors persist as industries mature? Standard models predict it will fade with formal governance and rivalry, yet in some sectors, it becomes a stable norm. Using a Veblenian Original Institutional Economics (OIE) lens, this paper develops a four-stage heuristic linking evolving uncertainty (radical, relational, coordination, durability) to distinct coordination logics. A mixed-methods study of the U.S. artisanal cheese industry (1975–2018) shows that collaboration became institutionalised through habituated practice, identity alignment, and moral commitment, later layered with formal supports. The framework clarifies how OIE best explains norm emergence and reproduction, while New Institutional Economics (NIE) helps account for codifying and scaling already-institutionalised norms. Quantitatively, peer networks shifted toward higher clustering and greater geographic localisation; qualitatively, mentorship and open exchange sedimented into professional expectations. Collaboration endures because it is morally meaningful, identity-affirming, and institutionally reproduced. Efficiency benefits may follow, but they do not explain its origin or persistence.

In this paper, we build a theoretical framework to better understand the polycentric governance of global socio-ecological challenges through the lenses of meso-institutional analysis. Climate change, deforestation, pollinator decline, and loss of soil fertility are examples of complex socio-ecological challenges caused by anthropic pressures at a global scale. These challenges result in intractable social dilemmas and absent or weak macro-institutions, posing questions on how subsidiary mechanisms of coordination can be adopted in a polycentric governance approach. Building on the meso-institutional framework and socio-ecological systems framework, we investigate the emergence and establishment of multi-stakeholder partnerships (MSPs), where businesses, governments, and civil society organizations try to address global challenges. Recognizing meso-institutional functions in MSPs allowed us to expand our theorizing of the polycentric governance of global socio-ecological challenges, looking at nested, interrelated, and multi-layered relations between multiple actors and organizations.

This article seeks to answer the question of how interbranch organisations (IBOs) can facilitate coordination among agents involved in transactions within agri-food chains. An IBO is a complex entity that establishes relationships among agents operating at different stages of a supply chain. The empirical analysis focuses on the Italian tomato supply chain and adopts a Process-tracing approach. The study is grounded in meso-institutions theory and demonstrates how the meso-institutional nature of the analysed IBO helps explain its role in establishing coordination among agents by performing the functions outlined by the theory. The institutional outcome of this relationship is the adoption of a contractual system that facilitates coordination itself. The contractual system identified provides an example of the articulation between the meso-institutional and micro-institutional levels.

Numerous studies show an association between military pressures and fiscal development, often based on cross-national correlations between wars and fiscal outcomes (e.g., tax ratios). However, investments in fiscal capacity may take time to yield higher tax revenues, obscuring the importance of factors that contributed to those investments. This article shifts attention from fiscal outcomes to the policymaking process. Using text-as-data techniques to analyse British parliamentary debates from 1803 to 1913, it offers new micro-level evidence of the relationship between military pressures and fiscal policymaking in the United Kingdom during the long 19th century. Our analyses show that military issues were associated with higher fiscal salience and lower contestation in tax debates. Qualitative analyses indicate that military issues were recurrently invoked to support the renewal of the personal income tax despite attempts to repeal it, confirming the close link between military and fiscal issues in shaping the modern British fiscal state.