Leopold's land ethic is now 75 years old —does it stand the test of time? Using an approach grounded in environmental ethics and the history and philosophy of science, Roberta Millstein offers a new interpretation and defense of Leopold’s land ethic in light of contemporary ecology. Roberta L. Millstein is Professor Emerit in the Department of Philosophy at the University of California, Davis, and is a Fellow of the American Association for the Advancement of Science.