In an era defined by complexity, the imperative for effective public policy has never been more pressing. As governments seek to address an increasingly multi-faceted issues which require concerted societal changes, behavioural public policy presents an opportunity to shape more informed, responsive, and ultimately more effective policies, programs and services.

Many, if not most, issues that governments seek to address involve human behaviour. Governments worldwide are increasingly embracing a people-centred and evidence-informed approach to policymaking, known as behavioural public policy. Applying a behavioural lens equips policymakers with a more realistic understanding of the issues at hand and provides evidence on potential policy consequences that may not be uncovered using traditional policy analysis methods that make assumptions about people and their behaviour that may not be true in practice. The strategic use of behavioural science enables policymakers to identify the most cost-efficient interventions, reducing risks associated with their policy decisions, and can help determine the success or failure of an initiative.

The consideration of human behaviour when developing policies is essential, and can determine the success or failure of an initiative, or impact the pace of change in our societies. For example, one aspect of reducing greenhouse gas emissions is changing household consumption choices (Whitmarsh, Poortinga and Capstick, 2021[1]), one aspect of increasing diversity is de‑biasing hiring practices (Murphy, Kroeper and Ozier, 2018[2]), and one aspect of reducing misinformation is limiting its spread (Lorenz-Spreen et al., 2020[3]).

This document provides practical guidance for government policy makers on how to achieve a systemic integration of behavioural science insights and methods into the policy making process. After a decade of advocacy and achievements, behavioural public policy looks set to endure. The time is right to gather lessons learned from across the global community of behavioural science experts in government and orient efforts for upcoming years.

The academic literature on what works to encourage the use of behavioural science evidence in government policy making is generally immature and inconclusive (Breckon and Dodson, 2016[1]; Welch-Ross and Fasig, 2007[2]). In one experienced academic’s view, “we are still in the early stages of understanding … how to effectively translate evidence from behavioural economics into meaningful policy outcomes” (Linos, 2023[3]). Furthermore, this relationship between behavioural science and policy is not straightforward, instrumental, or apolitical (Feitsma, 2019[4]).

Leaders who engage with behavioural science evidence and promote its use can be influential in embedding a behavioural approach. The principles in this section call for senior leaders to advocate for behavioural science, and for managers to actively build this support in their leaders.

Given the diverse policy topics to which behavioural science can be relevant, and the diverse evidence synthesis and production activities that can be useful to policy making, it can be helpful for governments to clearly establish where and how they want to use behavioural science. The principles in this section call for a clear strategy that is monitored over time, and which considers using behavioural science for both external policy (involving citizens, businesses, and other stakeholders) and internal policy (the processes and mechanisms of public administration itself).

Implementing a strategy to embed behavioural science into business-as-usual policy making takes effort and resources. Implementation will be more efficient and effective if there is a structure around how these resources and efforts are managed and organised. The principles in this section suggest an individual or team can be held accountable for mainstreaming behavioural public policy and be appropriately funded to do so.

Behavioural science experts and policy makers can shape and influence the partners, stakeholders, and structures around them to produce a better enabling environment for behavioural public policy. The principles in this section call for behavioural science to be embedded into standard processes and guidelines, for behavioural science activities to be conducted responsibly and openly to build citizens’ trust, and for behavioural science experts to inform the development of data structures that enable more efficient and effective problem diagnosis and solution development.

Behavioural science entails a complex body of knowledge and an array of evidence generation methods. The craft of policy making is similarly nuanced. Bringing behavioural science into policy making is therefore a difficult activity that requires a diverse range of skills. The principles in this section call for policy makers to know when behavioural science might help and to have sustainable and ready access to behavioural science experts. They also call for mechanisms to bring behavioural science evidence into the policy process in a way that is relevant and useful, and to share knowledge and practices among practitioners.

This report’s good practice principles are relevant for all governments. They identify categories of activity that deserve attention regardless of policy topic, context, or the government’s maturity in mainstreaming behavioural science. How these principles should be implemented in practice will, however, be dramatically different in different governments, and in different organisations within the same government – and these practices will also need to change over time. Practices that may be critical for establishing a position for behavioural science in the policy system may become irrelevant, or even detrimental, as the approach becomes part of business-as-usual.

This report has collated and synthesised guidance from the global behavioural science community on what has been effective so far in mainstreaming behavioural public policy. But these principles will need to be updated as policy challenges evolve, public administrations refine their operations, and behavioural science develops new insights and new methods. This section draws on active discussions in the field to suggest areas where we may see new good practices emerge in coming years.

Governments have, to different degrees and in different ways, expanded their use of behavioural science evidence over the last decade, enabling policies to be developed, tested, and selected with a more nuanced understanding of the people involved in achieving change. The principles in this report are based on the practices that policy makers and behavioural science experts have found to be effective over that time. The OECD will continue to participate in the global conversation about how and where behavioural science can help governments tackle complex policy challenges.