Deep sustainability is different from shallow or instrumental sustainability. Using limited resources more efficiently and substituting renewable for nonrenewable energy are necessary but are not sufficient. Deep sustainability addresses the root causes of unsustainability. It addresses the ethical, philosophical, and spiritual roots of human well-being that must sustain the ecological, social, and economic integrity of human relationships with each other and the other living and nonliving members of the Earth's integral community. Humanity has gone astray from its path of purpose during centuries of spiritual neglect, misuse, and abuse – in its continuing quest for unending economic growth and ever-greater economic wealth.