The most serious long-term threat facing the world is the danger that human actions are producing irreversible harmful changes to the environmental conditions that support life on Earth. If this problem is not overcome, there may be no viable world for our descendants to inhabit. Enormous changes to human lifestyles and cultural practices may be required to reach the goal of a sustainable level of impact on the environment - i.e., one that can be maintained indefinitely. Social science courses can aid in reaching this goal by teaching about environmentally responsible behavior. Such teaching should provide sound information and strengthen motivation and behavioral skills that are necessary to make the needed changes in behavior and lifestyles. This paper discussed the major obstacles to the goal of sustainability, describes a variety of motivational approaches toward accomplishing it, and proposes that we should view the achievement of sustainable living patterns as a superordinate goal - a war against the common enemy of an uninhabitable world.