Health policy makers aim to maximise potential health benefits from a proposed health policy or program under limited resources, especially in regions with relatively poor resources. In an aging population, people around the world are confronted with a fact that chronic diseases have accounted for 80% of mortality and consumed a significant amount of health resources. To tackle the financial burdens associated chronic disease, policy makers have to decide whether to allocate more health resources to curative care versus preventive care. Economic evaluation, namely cost-effectiveness analysis and cost-benefit analysis, has been proven to be a valuable tool to provide evidences on whether prevention and management through primary care can be cost-effective. For example, obesity can lead to a variety of serious chronic diseases. This presentation will share the experience of how Australia Government has combated obesity as a societal problem by implementing a wide range of preventive health policies. Health economist has certainly played an important role, using economic evaluation to inform the Government to identify and adopt most cost-effective health policies to combat obesity as best prevention.