This is an edited version of an address delivered on 1 September 2026 to Asian Evaluation Week, hosted by the Asian Development Bank at its headquarters in Manila, the Philippines.
This year’s Asian Evaluation Week theme, “Put Your Money Where Your Evidence Is”, is a powerful reminder that we have a responsibility to direct funding and resources towards programs that make a real difference.
At its core, evaluation is about answering a straightforward question: did a policy or program improve people’s lives?
That question is tricky to answer. We can observe what happened after an intervention was introduced, but we cannot directly observe what would have happened in its absence. Rigorous evaluation helps bridge that gap, because it gives us a credible counterfactual.
Evaluation moves us beyond assumptions. It helps us distinguish between correlation and causation.
Just as importantly, evaluation encourages humility.
Many policies that appear promising fail to deliver meaningful results when tested rigorously. Equally, some simple and inexpensive interventions produce benefits that exceed expectations.
Governments should be learning institutions. As stewards of the public good, we should be constantly improving our understanding of what works and why.
That principle has guided Australia’s efforts to strengthen evaluation across government, including through the Australian Centre for Evaluation.
It also underpins the Asian Development Bank’s longstanding commitment to improving development effectiveness through rigorous evidence and impact evaluation.
When I spoke at the Asian Development Bank and the Asian Development Bank Institute in Manila in July 2024, I argued that rigorous evaluation is essential for understanding whether development programs improve lives (see my addresses to the Asian Development Bank and the Asian Development Bank Institute).
Today, I want to focus on the next step.
Generating rigorous evidence is important.
Using rigorous evidence is essential.
Too often, evaluations conclude with a report. The big challenge is ensuring that findings influence decisions about which programs should be scrapped and which should be scaled up.
To achieve that, evidence must be integrated into the way institutions allocate resources.
In short, we must put our money where our evidence is.
Let me offer three examples.
First, evidence can help governments improve the fairness of the tax system. In the Democratic Republic of the Congo, researchers worked with local authorities in a large Congolese city to test different approaches to property taxation. Neighbourhoods were randomly assigned to either a progressive property tax schedule or a proportional one.
The progressive approach increased revenue by around 56% relative to the proportional schedule, and after it was scaled up alongside targeted enforcement, shifted the effective tax burden towards wealthier property owners.
Most importantly, the findings were used. The progressive tax schedule was subsequently expanded across the city, demonstrating how rigorous evidence can directly inform public policy.
Second, small interventions can sometimes make a big difference.
A study in Zambia considered the budgeting challenge for farmers who derive their income from one annual harvest and then spend it over the course of the year.
Researchers found that many households underestimated upcoming costs, not because they lacked information, but because they found it difficult to recall their past spending at the appropriate moment to inform their future spending plans.
The intervention was pretty simple: a randomly selected group of households were guided through a structured exercise to think about future expenses.
That small prompt increased savings by 15%, and allowed households to enter the annual “hungry season” with approximately one extra month of savings.
Households also invested more in farming, resulting in a 9% increase in crop revenue the following year. Effective policy does not always require complex solutions.
Third, evaluation helps us understand not only what works, but how long the effect lasts.
In Kenya, researchers looked at the issue of road safety, which is a major public health challenge in many countries where traffic laws exist on paper, but enforcement can be inconsistent.
In this trial, Kenyan minibus drivers were randomly assigned to receive financial incentives for safer driving, measured using vehicle monitoring technology.
The incentives reduced dangerous driving behaviours. For example, drivers who received the incentive reduced speeding by 29%. But the study also found that the effects diminished once the incentives were removed.
No policy lasts forever, and a rigorous randomised trial can help get at impact duration as well as impact magnitude.
The Asian Development Bank has been a leader in building evaluation capability across the region, supporting impact evaluations, developing practical guidance and fostering collaboration between governments and researchers.
In the Philippines, researchers tested computer-assisted learning in remote schools and found meaningful improvements in mathematics achievement.
In the People’s Republic of China, a randomised evaluation of a village banking program showed that access to microcredit increased incomes and reduced poverty.
In Bangladesh, phone-based learning interventions demonstrated that parents can play a powerful role in supporting children’s education, even when schools are disrupted.
And another Bangladesh experiment showed that community participation can improve access to safe drinking water, but only when decision-making processes are designed well and local communities have meaningful incentives to engage.
Likewise, many of the social policy challenges faced by countries across Asia and the Pacific are shared. Questions about tax capacity, road safety, poverty reduction, service delivery and economic opportunity arise in many different contexts.
Not every result will transfer perfectly from one country to another. But a rigorous study from overseas can often be more useful than low-quality evidence produced locally.
When countries share findings and replicate successful approaches, evidence becomes a regional public good.
A sign of the expansion in this public good is the growth of randomised trials. In the 1990s there were fewer than 25 randomised trials from developing countries published globally each year. By 2012, there were 274 published.
All up, the Abdul Latif Jameel Poverty Action Lab at MIT has led more than 2,600 randomised trials. The American Economic Association’s randomised trials registry lists more than 12,000 registered social science trials, with over 1,600 added last year alone.
The Australian Government, through the Australian Centre for Evaluation, is also doing its bit to generate — and use — rigorous evaluation evidence.
So far ACE has directly supported seven randomised trials, with four more in progress, and more planned. These evaluations have provided evidence on a range of policy problems, from the design of employment services to improving government service delivery and reducing regulatory red tape. And in each case, the evidence fed back into the government’s decision-making process.
ACE has also built a professional network for public servants — the Evaluation Profession — which has grown to more than 8,000 members. A public repository of Australian government evaluations now hosts over 200 publications, and growing.
Fifteen years ago, randomised experiments dramatically improved the way aid workers distribute bed nets to prevent malaria. A critical question was whether it was better to charge a small co-payment because people who paid would be more likely to use the nets.
Researchers established that people who received free bed nets were just as likely to use them as those who made a co-payment. But because they were free, many more people took them up.
That translated into practice and has helped save thousands of lives across Africa and the rest of the developing world.
This is just one example of why we need to put our money where the evidence is.
The goal of evaluation is better lives.
If we are serious about putting our money where our evidence is, then evidence cannot be treated as an afterthought. It should inform the decisions that matter most.
Because the burden of ineffective policy falls upon people.
We have a responsibility to families who depend on public services. To communities that need opportunities. And to citizens who rightly expect governments to be constantly learning and improving.
Evaluation will not eliminate uncertainty, but it gives us a rigorous method to reduce uncertainty over time.
Evidence matters — because it helps us build a better future for those who need government most.
Editor’s note: The Australian Centre for Evaluation (ACE) was established in the Treasury portfolio in July 2023. The government’s 2023 International Development Policy said that DFAT would work closely with it to further ensure the rigour of its evaluation practice. Completed ACE evaluations to date have been in domestic policy areas such as employment services, social services and health.
