Given that human behavior is the cause, directly or indirectly, of most of the detrimental environmental change that is the focus of this book, a major challenge is to find ways to induce behavioral change to make it more environmentally friendly. Behavior in this context includes that of individuals and groups, and the groups of interest range from social, political, and corporate entities to neighborhoods, towns, and nations. The challenge is especially keen for psychology, the science that deals most directly with behavior and behavior change. Meeting the challenge is unlikely to be easy. As Ruckelshaus (1989) put it, speaking only of the problem of controlling greenhouse warming: “It means trying to get a substantial proportion of the world’s people to change their behavior in order to (possibly) avert threats that will otherwise (probably) affect a world most of them will not be alive to see” (p. 166).