Abstract
Founded on Agency Theory, Upper Echelon Theory, Stakeholder Theory, and Resource Dependence Theory, this study explores how different aspects of board diversity namely gender, nationality, ethnicity, and professional background influence corporate social responsibility (CSR) disclosure among non-financial firms in Nigeria. Using a panel methodology involving 15 listed companies, with a total of 150 firm-year observations from 2014 to 2023, the study applies the panel ordinary least squares (OLS) estimation technique. Post-estimation diagnostic tests are conducted to ensure the robustness of the results. Additionally, a trend analysis was performed to assess the trajectory of CSRD practices over the study period. The empirical findings indicate that ethnic and nationality diversity have a positive impact on CSR disclosures. Conversely, gender and professional background diversity are negatively and significantly related to CSR disclosures, suggesting agency-related issues within diverse boards. The trend analysis further reveals a steady annual increase of approximately 1.8% in CSRD, reflecting growth in sustainability reporting practices in Nigeria. The study offers both theoretical insights and practical recommendations, emphasizing that regulators in emerging economies should move beyond symbolic diversity reporting. Instead, they should promote systems that enable diversity to play a meaningful role in CSR-related decision-making processes. The study underscores that CSRD outcomes are not solely driven by diversity but are significantly influenced by how corporate boards effectively integrate diverse strategies into governance processes.