Advancing Sustainability in International Arbitration: The Development of the Arbitration Sustainability Index (ASI)

ABSTRACT Pressure is mounting for international arbitration to align with global sustainability expectations, yet scattered initiatives—virtual hearings, e‐bundles, diversity pledges—offer no coherent metric of success. This article proposes the Arbitration Sustainability Index (ASI), a voluntary soft‐law instrument that converts the UN Sustainable Development Goals and ESG benchmarks into a tri‐partite scorecard of arbitration's environmental, economic, and procedural/social performance. Through doctrinal analysis of leading rules, treaties, and case law, nine quantifiable indicators are distilled and embedded in a weighted 35–30–35 scoring model. A branching‐logic scenario and proof‐of‐concept simulation illustrate the ASI's capacity both to diagnose carbon‐light, cost‐proportionate, and inclusive procedures and to spur reform via reputational competition rather than legal compulsion. By standardizing data collection and enabling cross‐institutional comparison, the ASI equips scholars with a testable construct, practitioners with an audit tool, and policymakers with an evidence base for soft‐law or legislative nudges. Future empirical studies will refine weightings and track behavioral uptake, advancing the ASI toward a widely recognized sustainability benchmark for arbitration.