popular research in behavioural economics (2).2 This body of work potentially adds further justifications for government interventions. According to this view, there are situations in which people act on the basis of what has been called “bounded rationality”: because people may not at all times be able (or willing) to undertake all the necessary calculations to find the choice that maximizes their lifetime utility, they may find ways to simplify choices. Or individuals’ preferences might not follow the pattern posited by standard welfare economic theory. As a result of any of these imperfections the actions may then well differ from what would have been the perfect rational choice, but the way in which they differ may be predictable. This could offer an opportunity for governments to target those predictable “failures” in decision-making and to help people take those decisions that they would have chosen, had they been in a position to do so. The standard welfare economic rationale is first discussed below, then the behavioural economics perspective. The discussion will be illustrated with the help of relevant social determinants of health examples.