From Black to Green: Sustainability in Audit

The global transition toward sustainable development is reshaping every aspect of public governance, and public sector auditing is no exception. As governments commit to ambitious climate targets, green investment programmes, and circular economy policies, audit institutions face the challenge of developing methodologies and competencies that can effectively assess whether these commitments are being translated into meaningful action. The shift from "black" — traditional financial auditing focused on monetary flows — to "green" — sustainability-integrated auditing — represents one of the most significant transformations in the history of public sector oversight.

Sustainability auditing requires auditors to evaluate dimensions of government performance that were historically outside the scope of traditional audit engagements. This includes assessing the environmental impact of government operations, evaluating the effectiveness of climate mitigation and adaptation programmes, reviewing the reliability of greenhouse gas emissions reporting, and examining whether procurement policies adequately incorporate environmental criteria. Each of these areas demands new technical competencies and methodological approaches that go beyond conventional financial and compliance auditing.

Several OECD member countries have made significant progress in integrating sustainability into their audit frameworks. The Netherlands Court of Audit has developed comprehensive approaches to environmental performance auditing, while the UK National Audit Office has examined government progress against climate targets. The Brazilian Court of Accounts has pioneered the use of satellite data to audit deforestation control programmes. The OECD Auditors Alliance serves as a platform for sharing these innovations, enabling audit institutions to learn from one another's experiences and adapt successful approaches to their national contexts.

The transition to green auditing also raises important questions about the role of audit institutions in the broader sustainability ecosystem. Should auditors simply assess compliance with existing environmental regulations, or should they take a more proactive role in identifying gaps in environmental governance and recommending systemic improvements? The Alliance continues to explore these questions through working groups and thematic discussions.