Aldo Leopold: A Fierce Green Fire (OUP; 1999) remains the only biography for the general public on Leopold. It was praised for being concise and readable, and written in the context of the history of American conservation. In a second edition, Marybeth Lorbiecki has added new chapters on Leopold's legacy-the ripple effects of the ecological knowledge, ethics, and leadership he instilled in his wife's family in the Southwest, his children, graduate students, organizations-and on his relevance today. In a new introduction, Lorbiecki explains why Leopold is still so relevant, focusing on the new ecological challenges we face and the myriad of ways his work influences us today, including phenological studies he started at the Shack and their role in proving climate change, and responses to these challenges based on a land ethic. New chapters focus on the Leopold children and their contributions to the land ethic and ecology in their different scientific fields, Leopold's key graduate students and their contributions to various fields, and the recent activities of various organizations that Leopold helped launch.