It might seem unnecessary to define what a person is, but the issue of personhood has been a longstanding source of debate. The scope of personhood has been questioned in many applications, including human slavery, right to life and right to end life, animal rights, bioethics, corporate rights, and theology. It is believed the question will arise again as robots and artificial intelligence become more sophisticated and ingrained in our culture. What makes a person, and who gets to define personhood? Viewpoints in this volume address this fascinating topic from a number of angles.