For decades, the idea of sustainable development (or sustainability as it has recently become known) is something that world leaders say they are committed to but find difficult to put into practice. The Australian government, for example, has had a National Strategy for Ecologically Sustainable Development (NSESD) since 1992, yet the country is less sustainable today than when the strategy was adopted because of declining environmental quality. This is despite the fact that the principles of ecologically sustainable development have now been enshrined in numerous pieces of legislation, policies, and plans at all levels of government for more than a generation of Australians. The reasons for this policy implementation failure are numerous, but key among them are a lack of consistent leadership, clashing policy priorities, the absence of much needed institutional restructuring, and inadequate resourcing. Australia is not alone in this failure, however, with similar experiences documented around the world. This chapter reviews the Australian experience and draws from it lessons that could be useful in many other countries. The takeaway message is that national governments need to “walk the walk,” not just “talk the talk.”