This chapter does two things. First, it discusses the equivalence principle as one traditional consideration of justice in exchange. The equivalence principle holds that a certain exchange can only be just if the two goods exchanged are of equal value. As it turns out, exchanges at the market price are particularly suited for actually meeting this principle. Second, the chapter fleshes out the implications of this. Notably, if exchanges at the market price are equivalent, that is, if they are justice-preserving with respect to the values exchanged, then rising monetary inequality (as one potential consequence of millions of individual exchanges) cannot be a problem for market exchanges. The chapter uses the example of the labor market to illustrate this reasoning.