<p>This study examines the relationship between sustainability reporting and firm value, financial performance, and risk among Vietnamese firms, utilising the Global Reporting Initiative (GRI) standards. By analysing sustainability disclosures from the 100 largest firms by market capitalisation listed on the Hanoi and Ho Chi Minh stock exchanges as of 31 December 2023, the research employs multiple regression models to investigate the influence of sustainability disclosure on firm value (Tobin's Q), firm performance (ROA and ROE), and risk (Z-Score) during the 2021–2023 period. The findings reveal a relatively low level of sustainability disclosures among Vietnamese firms. Nevertheless, the study establishes a positive relationship between sustainability disclosure and both firm value and financial performance, alongside a negative relationship with firm risk. These results support the hypotheses and underscore the importance of sustainability disclosures in shaping corporate outcomes. As the first comprehensive analysis of the impact of sustainability disclosure in Vietnam using GRI standards, this research provides valuable insights for corporate managers and policymakers. It highlights the strategic importance of integrating sustainability disclosures into corporate practices to enhance firm value, improve financial performance, and mitigate risks, particularly during periods of financial uncertainty. For corporate finance managers, these findings emphasise the necessity of prioritising sustainability reporting to align with investor expectations and achieve long-term stability. Furthermore, the study stresses the broader societal implications of enhanced transparency in sustainability practices. By fostering more resilient economies in emerging markets like Vietnam, policymakers can utilise sustainability disclosures to encourage sustainable business operations, ultimately promoting improved social and environmental outcomes.</p>