Global biodiversity is in the midst of a mass extinction driven by rapid human population growth and over-consumption of resources. These forces drive habitat loss, pollution, invasive species, climate change, and the many other proximate causes of species losses. The study of these forces, and how they can be mitigated to preserve biodiversity, is the responsibility of scientists engaged in the field of conservation biology. My guest, Thomas Lovejoy, is a founding scientist of this field, and often referred to as the Godfather of Biodiversity. Tom received B.S. and Ph.D. degrees in biology at Yale. He then held many prominent positions related to conservation, including with the World Wildlife Fund, the Smithsonian Institution, the World Bank, and the Inter-American Development Bank. He served in many scientific advisory roles for the U.S. government, and as a Conservation Fellow and Explorer at Large for National Geographic. Tom is a professor in the Environmental Science and Policy department at George Mason University and a senior fellow at the United Nations Foundation. He is the recipient of numerous environmental awards, including the Tyler Prize for Environmental Achievement and the Blue Planet Prize. He is also a Fellow of the American Association for the Advancement of Science, the American Academy of Arts and Sciences, the American Philosophical Society, the Linnean Society of London, and the American Ornithologists’ Union.