Sometimes a government looks at a price—say, the rent for an apartment or the wage workers earn—and decides it’s too high or too low. The feeling is human: make housing affordable, give workers a living wage. But when a law overrides the market price, the world doesn’t simply obey. Like putting a lid on a boiling pot or propping up a sagging floor, price controls can hold things where we want them for a moment—but the steam and the pressure often escape in ways nobody intended. This chapter shows you exactly how those unintended consequences unfold, and why they happen almost every time.