The lessons learned from over 20 years of obesity prevention efforts in Australia and New Zealand are presented. The obesity epidemic started in the 1980s but poor monitoring systems meant the rise in obesity prevalence initially went undetected. In the 1990s, experts started advocating for government action; however, it was the rapid increase in media reports on obesity in the early 2000s which created the pressure for action. Several, comprehensive reports produced some programme investment but no regulatory policies were implemented. The powerful food industry lobby ensured this lack of policies on front-of-pack food labelling, restrictions on unhealthy food marketing to children, or taxes on unhealthy foods. The New Zealand government even backpedalled by rescinding healthy school food guidelines and withdrawing funding for the comprehensive national obesity strategy. In 2007, Australian Governments started a major long term-investment in preventive health in order to improve economic productivity. Other positive initiatives, especially in Australia, were: the establishment of several advocacy organizations; successful, long-term, whole-of-community projects reducing childhood obesity; a national knowledge exchange system for practitioners; and some innovative programmes and social marketing. However, despite multiple reports and strong advocacy, key recommended regulatory policies remain unimplemented, largely due to the private sector interests dominating public policy development.