Sinnott-Armstrong here provides an extensive survey of the difficult subject of moral beliefs. He covers theories that grapple with questions of morality such as naturalism, normativism, intuitionism, and coherentism. He then defends his own theory that he calls "moderate moral skepticism," which is that moral beliefs can be justified, but not extremely justified.
Walter Sinnott-Armstrong (born 1955) is an American philosopher specializing in ethics, epistemology, neuroethics, the philosophy of law, and the philosophy of cognitive science. He is a Professor of Practical Ethics in the Department of Philosophy and the Kenan Institute for Ethics at Duke University.
Very informative book with interesting insights into several competing epistemic philosophies. A tad bit too much repetition of his stances, however, that didn't detract too far from the overall quality.
Sinnott-Armstrong does a fantastic job articulating his position and handles the opposing arguments consistently and thoroughly. While the book and subject matter are quite dense, Sinnott-Armstrong's writing style is very coherent. Moral Skepticisms is one of my favorite contemporary books on ethics.