Board diversity and sustainability performance in Indonesia firms

Abstract

This study examines the effect of board gender diversity (BDG) on sustainability performance and whether ownership concentration and sustainability assurance moderate this relationship. Although prior ESG research has examined board diversity, it provides limited explanation of why Board Gender Diversity may be more or less effective under different governance conditions, particularly in emerging markets. Indonesia offers a relevant setting because listed firms commonly exhibit concentrated ownership, while ESG reporting, assurance, and stakeholder accountability are still developing. Using a quantitative approach, this study analyzes 150 firm-year observations from firms listed in the IDX ESG Leaders Index during 2020-2024, selected through purposive sampling based on the availability of complete annual and sustainability reports. Panel regression with interaction terms shows that BGD improves sustainability performance. However, this effect weakens as ownership concentration increases and strengthens when sustainability assurance is present. The study’s novelty lies in demonstrating that the effect of Board Gender Diversity is a conditional, internal ownership power constrains its effectiveness, whereas external assurance strengthens it.