The principle that prevention is better than cure has been a cornerstone of public health policy for well (0) OVER a century. Vaccination programmes, sanitation improvements, and public awareness campaigns have all contributed to dramatic reductions in the prevalence of infectious diseases. 1 it not been for these interventions, life expectancy in many parts of the world would be considerably lower than it is today. In spite of 2, there remains a persistent tendency among governments to prioritise treatment over prevention when it comes to allocating healthcare budgets. This is due, at least 3 part, to the fact that the benefits of preventive measures are often invisible — it is difficult to quantify the number of illnesses that 4 not occur precisely because they were prevented. Furthermore, it may be years 5 the results of prevention programmes become apparent, making them a less attractive option for politicians focused on short-term outcomes. There has, however, been a growing recognition that this approach is 6 from sustainable. With ageing populations placing an ever-greater strain on health services, it is becoming increasingly clear that 7 more is invested in prevention now, the costs of treating chronic disease will continue to spiral. The question is not 8 prevention works — the evidence for that is overwhelming — but whether governments have the political will to act on it.