The credibility of corporate sustainability rests on one foundation: reliable data. Without it, even the most ambitious environmental or social commitments lose meaning. New joint research from ACCA and the Internal Audit Foundation makes the case that robust internal controls are essential to trustworthy sustainability reporting, and that accountants and auditors are best placed to make it happen.
From ambition to assurance
The report, Internal control over sustainability data, highlights how familiar principles of financial control can—and should—apply to non-financial information. Sustainability metrics often originate outside finance, in areas where control awareness and documentation are still maturing. Without ownership and verification, inconsistencies quickly creep in.
Helen Brand, chief executive of ACCA, calls trust in sustainability data “vital to driving a more sustainable world”. That trust, the report argues, depends on the same rigour that underpins financial statements. As sustainability disclosures move closer to mainstream assurance through frameworks such as the ISSB standards and the EU’s Corporate Sustainability Reporting Directive, the expectation for accuracy is becoming unavoidable.
Control starts with leadership
The research emphasises one point above all: sustainability objectives must be part of core business strategy. When leadership treats these goals as strategic, supported by measurable key performance indicators, control processes naturally follow. When they are treated as side projects, reliability suffers.
Anne Kiem, chief executive of the Chartered Institute of Internal Auditors, warns that weak internal control can do more than damage credibility. It can invite accusations of greenwashing. Internal audit, she says, has a critical role in providing assurance that sustainability-related data is both “robust and accurate”.
Getting the basics right
Implementing control over sustainability data does not require a complete system rebuild. Mapping data flows, assigning ownership and defining evidence sources go a long way. Cross-functional collaboration between finance, audit, operations and sustainability leads ensures that control points are understood and repeatable.
Technology can help consolidate and monitor information, but judgement remains central. Automated systems can track carbon use or supplier data, yet human oversight determines whether inputs are meaningful and material. The report underlines that professional scepticism, already second nature to accountants, must extend into sustainability assurance.
The capability gap
Another recurring theme is skills. Many employees collecting sustainability data lack experience in documentation, sign-off and version control. A modest investment in training can close these gaps quickly. The report suggests that building “control consciousness” across teams delivers immediate improvements in data quality and transparency.
A growing mandate for the profession
For accountants and auditors, this is an expanding frontier of relevance. Applying proven control frameworks to sustainability data strengthens governance and aligns with the profession’s public-interest duty. It also anticipates new assurance requirements from standard-setting bodies such as the International Auditing and Assurance Standards Board.
In practice, this means treating sustainability metrics with the same seriousness as revenue or cost data – subject to defined processes, clear sign-off and periodic review. Organisations that start embedding those habits now will be better prepared when mandatory assurance becomes the norm.