Every day around the world, governing bodies enforce new policy measures to improve people’s health and well-being, reform education or regulate the economy. The process leading to new policy is very often the same. A societal problem emerges getting media and political attention, then a handful of people in charge consult experts, sometimes ask the latter to write reports, and based on their recommendations design a reform or policy intervention (supposed) to fix the problem. In spite of such decisions will potentially impacting the lives and behavior of millions of citizens, the paradox is that very few countries rely on behavioral and brain insights and systematic testing prior to implementing new policy. When possible governments should rely on randomised control trials (RCTs) –i.e. measuring the effect of multiple variations of a policy intervention on the behavior of several large groups of individuals against a control group with no intervention whatsoever – to design and test new policy. RCTs can inform public policy, spot errors, and help government design and implement cost efficient policy before scaling them. In such a difficult economic and social context, public organizations can no longer afford –at the financial and human levels- not to have a return on investment on the money invested in research on behavioral and brain sciences applied to policy especially when it can allow to improve the life of the citizens.