The Evidence Gap: OECD research on due diligence in practice

By Ben Rutledge

July 2026

Image: Stones laid out on grass as a map of the world

“The problem is not a shortage of indicators. It is a shortage of evidence that decision-makers can actually use and trust.” Following the publication of the OECD’s inaugural Responsible Business Outlook, The Outcome Gap’s Head of Policy, Ben Rutledge, explores why companies increasingly need to move beyond commitments to demonstrating that those commitments are driving change.

Fifty years after the OECD Guidelines for Multinational Enterprises were first adopted, the OECD published its inaugural Responsible Business Outlook on Making Commitments Count at the end of June.

It’s the first global stock take of how responsible business conduct is reflected in company practice and government policy - drawing on public disclosures from the world’s 10,000 largest listed companies and policy reviews across 52 countries.

The headline finding is not that companies lack public commitments. Indeed, sixty-nine per cent disclose at least one responsible business conduct commitment. The gap appears when we look for implementation and results: fewer than 20% report evaluating environmental and social risks among suppliers; only 7% report integrating social supply-chain policies into purchasing practices; and just 3% appear to have disclosed improvements in supply chain health and safety.

The 3% figure does not prove that 97% of companies failed to improve conditions. It shows that, from public information, it is impossible to tell whether conditions really improved.

This is the evidence gap.

The OECD says more relevant comparable data is urgently needed to assess uptake and outcomes of due diligence. 

Current metrics tend to provide an indicative and approximate picture of due diligence. And too many indicators still measure the basics: policies adopted, training delivered or audits completed. These may be necessary, but they do not tell us whether risks were reduced, harms prevented or people’s circumstances improved.

Without credible metrics and data, companies do not know whether due diligence is actually working. Or whether the investment in sustainability and risk management is paying off. 

The answer is not simply more data. The OECD’s accompanying work on due-diligence reporting requirements shows how inconsistent reporting processes and data formats can create duplication throughout supply chains, without necessarily producing information that management can act on.

The problem is a shortage of credible evidence that links what companies are doing to what is actually changing - evidence that decision-makers can trust and act on.

What counts as credible evidence?

There is no single set of indicators that can demonstrate effectiveness across every human rights or environmental issue. The evidence needed depends on the risk, the operating context, the intended outcome, and the role a company can realistically play in achieving it.

The starting point should therefore not be the data a company already collects, but the change it is trying to support. As our previous articles on Theory of Change have argued, this means working backwards from an intended outcome, making assumptions about how change will happen explicit, and asking: “What evidence do we have that this will work?” It also means drawing on different forms of evidence, not only audit data, but also qualitative insights and the experiences of affected workers and stakeholders.

The OECD similarly calls for outcome-oriented indicators and more relevant and comparable data, which can also help drive more meaningful reporting. But comparability should not come at the expense of context. Companies need to be honest about their sources, methods, coverage and limitations, and ensure that the depth of measurement is proportionate to the severity of the issue.

The regulatory signal is strengthening

This expectation is increasingly reflected in law and policy.

The OECD recently assessed 21 legislative measures on social and environmental due diligence legislation across 11 different jurisdictions, revealing some clear global trends.

Despite differences in thresholds, a growing number of policy frameworks ask companies to do far more than simply describe their due diligence procedures. Regulators increasingly expect businesses to build systems that track implementation, monitor results, review whether their measures are effective and appropriate, and assess whether their due diligence is actually working in practice.

For our team, this is where the practical work begins. Companies must now figure out how to move beyond setting up basic processes and writing policy commitments, towards establishing clear impact pathways and robust KPIs, and gathering useful evidence about what is actually changing on the ground.

This global convergence reinforces a principle at the heart of The Outcome Gap's approach: impact measurement is not an isolated, end-of-year reporting exercise, but a fundamental component of effective due diligence. Whatever language a jurisdiction uses, the underlying expectation is the same - understand your impacts, act on them, test whether that action is working, and show what you've learned.

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What are you doing to overcome the evidence gap? Get in touch: hello@theoutcomegap.com