The concept of sustainability has become highly important in the business community, academia, and government. Both in the U.S. and internationally, sustainability is used as a guiding principle in policy decision-making, development planning, natural resource management, advocacy coalitions, and within various professional and academic fields. Despite sustainability's prevalence among so many actors and organizations, the concept itself remains highly contested. This book defines and delineates exactly what sustainability does and does not mean. The authors carefully examine the various ways that the concept of sustainability is used. As numerous political theorists have demonstrated, the way we define and use a concept has important consequences for the material outcomes of that concept. In policy, for instance, we can immediately identify the importance of defining certain terms and making decisions within the parameters of those terms. By examining the myriad uses of the concept of sustainability, we can identify the potential pitfalls that can occur when a concept is spread too thin, over the course of the book, the authors seek to generate a more operationally clear definition that helps to stress the importance of moving more aggressively toward a change in our way of living.