Kominers discussed how tools, methods, and approaches from market design can be used to address issues of inequality. He illustrated key market design principles through a case study on the design of school choice mechanisms. Strategy-proofness—a guarantee that each participant's optimal strategy is to reveal his or her preferences truthfully—promotes equal access by reducing the benefits of strategic sophistication. Elimination of justified envy—ruling out the possibility that someone may prefer the outcome of someone else who has lower priority—both promotes fairness and ensures market stability. Thickening a market—incentivizing full participation in the market mechanism—improves transparency, reduces corruption, and makes outcomes more efficient.