Three profound transformations are under way on Earth right now. Climate change is real and is pushing us toward managing the planet as a whole. Urbanization—half the world’s population now lives in cities, and eighty percent will by midcentury—is altering humanity’s land impact and wealth. And biotechnology is becoming the world’s dominant engineering tool. In light of these changes, environmentalists are going to have to reverse some longheld opinions and embrace tools that they have traditionally distrusted. Only a radical rethinking of traditional green pieties will allow us to forestall the cataclysmic deterioration of the earth’s resources.