Before revision:  We show that fairness, meaning the absence of justified envy, can be achieved together with efficiency and individual rationality (respect for property rights). Our approach requires standard assumptions on agents' preferences, and is compatible with quantity constraints on allocations. The main application of our results is to school choice, where we can simultaneously achieve fairness, efficiency, and diversity-motivated quantity constraints .
After revision:  We show that fairness, meaning the absence of justified envy, can be achieved together with efficiency and individual rationality . We introduce a competitive equilibrium approach with price-dependent incomes obtaining the desired properties .