The post-war development of environmentalism has been driven by advocates who believe that humans are morally, politically and personally responsible for the health of the planet. How do people develop morals and values which lead them to become stewards of the environment? How do some of these people become 'environmental exemplars' - those who give significantly of themselves to environmental causes? This study considers these issues and contributes to the literature on moral identity. In-depth interviews were conducted with environmental exemplars concerning their childhoods, primary influences, environmental commitments, and the development of their thinking and worldviews. Preliminary results suggest that time spent in nature as a child, powerful experiences related to the environment, and environmental role models are among the factors that contribute significantly to the formation of an environmental moral identity. These results emphasize the value of exposing children to the natural world in order to foster values of environmental stewardship.