Do moral questions have objective answers? This book explains and argues for relativism, emotivism and moral skepticism. In its view, moral disagreements are like disagreements about what to pay for a house: there are no correct answers ahead of time, except in relation to one or another moral framework. Independently, Judith Jarvis Thompson examines what she takes to be the case against moral objectivity, and rejects it: she argues that it is possible to find out the correct answers to some moral questions. In her view, some moral disagreements are like disagreements about whether the house has a ghost. Harman and Thompson then reply to each other. This exchange should be useful to all students of moral theory and meta-ethics.