Andrew Linzey is a lecturer in theology at the University of Oxford in Oxford, England . He has written widely on animals and Christianity, including a series of liturgies for animals.

Calvin DeWitt is a professor at the Nelson Institute for Environmental Studies at the University of Wisconsin-Madison. He is concerned with the ethics of farming and uses of the natural environment, including animals. He is co-founder of the International Evangelical Environmental Network.

Regis John Armstrong is a professor of historical theology and spirituality at Catholic University of America in Washington, D.C. A Capuchin Friar Minor, he is an expert on St. Francis of Assisi.

Eric Reinders is an associate professor of religion at Emory University in Atlanta. He has written about Buddhist attitudes toward animals.

Kerry Walters is a philosophy professor at Gettysburg College in Gettysburg, Pa. With Lisa Portmess, she co-authored two books, one about the history of religious vegetarianism and the other on the history of ethical vegetarianism.

Lisa Portmess is a philosophy professor at Gettysburg College in Gettysburg, Pa. With Kerry Walters, she co-authored two books, one about the history of religious vegetarianism and the other on the history of ethical vegetarianism.

Kimberley Christine Patton is a professor of the comparative and historical study of religion at Harvard University in Cambridge, Mass., where she has taught a course in animals and religion. She is co-editor of A Communion of Subjects: Animals in Religion, Science & Ethics (2006).

Bernard Unti is senior policy adviser and special assistant to the president of the Humane Society of the United States. He holds a doctorate in U.S. history and is the author of Protecting All Animals: A Fifty-Year History of the Humane Society of the United States.

Andrew Rowan is executive vice president for operations at the Humane Society of the United States and CEO of the Humane Society International. He has a doctorate in biochemistry, is a Fellow of the American Association for the Advancement of Science and is former director of the Tufts University Center for Animals and Public Policy.