How should a new political economy conceive of the role of markets in a just society? Markets clearly play an important role in efficiently allocating labor and goods, disseminating information, enabling cooperation among people who disagree with one another about how to live, and allowing individuals ‘ choices about where to direct their talents and resources. But acknowledging that markets play an important role does not mean that this role is simple or conforms to the status quo in capitalist countries like the United States. In this essay, I draw on classical and modern ideas to defend a limited role for markets that is tempered by democratic concerns.