The book argues that by relying on moral incentives it is possible, in principle, to separate the organizational advantages of the market from its distributional  disadvantages. In theory, we can imagine a politico-economic system that distributes income equally (or on some other principle) but has all the efficiency characteristics of a capitalist market system. This shows that the market can provide an institutional mechanism for realizing ideals of distributive justice. The book provides a theoretical model of the system, identifying its requirements. It then offers arguments from empirical social science about why the model should work under appropriate conditions.