Policy Design under Capacity Constraints: A Comparative Analysis of Capacity-Design Fit

Why do states with similar policy instruments produce divergent implementation outcomes? This paper proposes the Capacity–Design Fit framework, specifying three mechanisms, namely knowledge-processing pathways, operational routines, and legitimation channels, through which governance capability shapes feasible policy architectures. Comparative analysis of 15 social protection programmes across eight countries in the Middle East and North Africa, combining hierarchical cluster analysis with fuzzy-set Qualitative Comparative Analysis, identifies three cross-nationally recurring design archetypes. Implementation effectiveness varies with capacity–design congruence rather than with design complexity: state capacity, contextual stability, and administrative capacity are each individually necessary for high effectiveness, whereas design complexity is neither necessary nor sufficient. The evidence is exploratory and the framework generates propositions for validation across additional cases and policy domains.