Advancing the discourse: a next-generation value chain-based taxonomy for circular economy key performance indicators

The growth of interest in circular economy (CE) has been accompanied by different approaches to measurement of CE outcomes and impacts, leading to a wide portfolio of indicators with varying degrees of overlap, inconsistency, and convergence. The aim of this paper is to propose a unifying framework for CE indicators, as the next generation of CE taxonomies. We first undertake a scoping review of 59 review papers on CE indicators using manual and computational methods (i.e., topic modelling) to inform the taxonomy structure and content. As a result, we report on 11 clusters of approaches that have been attentive to different dimensions of CE (e.g. horizontal value chain, vertical scale of operation (macro, meso, micro), impact category (economic, biophysical, social), material vs product focus, etc.). Highlighting the strengths and weakness of these approaches, we identify gaps in dimensions related to horizontal and vertical scales of measurement, and propose an agnostic, integrative framework that builds on the scientific foundations of previous research, within a more systemic and comprehensive taxonomy. This taxonomy could be used as a guiding framework or heuristic for regulators, both nationally and internationally, and for practitioners to undertake a comprehensive measurement and assessment of CE related interventions and initiatives at scale.