A framework for fragility

This paper develops a general framework for understanding and measuring fragility, applicable across disciplines. Although the concept of fragility is widely used in research and policy, its definition and measurement remain contested even within individual fields. The framework offers a structure for thinking about fragility by examining the process through which an object fails. We conceptualize fragility as the ease of failure, distinguishing it from risk and resilience, and analyse five measures: critical stress, damage condition, conditional probability, unconditional probability, and composite index. We also provide policy guidance on developing fragility measures and illustrate the crucial role of defining failure to measure fragility and inform policy.