Book excerpt: Most of us hope to do what morality requires of us. But what if we can't figure out what it does require? A soldier may know that morality requires him not to kill an innocent civilian but he can't tell whether the driver of a suspicious car is an innocent civilian or a terrorist about to detonate a bomb. Holly M. Smith addresses this problem in Making Morality Work by asking whether we should reject moral codes that can't be used by anyone hampered by inadequate information. When considering questions of morality, we call on moral theories to play both a theoretical and a practical role. These theories provide accounts of what makes actions right or wrong, and also provide a standard by which agents can guide their own conduct. It is usually assumed that a single theory can serve both roles, but limited knowledge often prevents people from using traditional normative theories to make decisions. Smith examines three major strategies for addressing this 'epistemic problem' in morality before developing an innovative solution that overcomes the weaknesses of prior approaches. Making Morality Work opens a path towards resolving a deep problem in moral life.