When we speak of the power of markets, we are referring to a form of structural power. A wheat farmer who wants to earn more income to pay for his daughter’s college tuition may decide to plant more wheat. But if other farmers plant more as well (and demand does not change), market forces may reduce his income and affect her educational prospects. In a perfect market, the agent has no pricing power. Millions of other unseen agents making independent choices create the supply and demand that determine the price. This is why poor countries that produce commodities are often subject to wide variations in their terms of trade. But if an agent can find a way to change the structure of a market by introducing an element of monopoly (a single seller) or monopsony (a single buyer), she can gain some power over price. She can do this by differentiating her product through advertising, creating brand loyalty, picking a special location, and so forth. Or in the case of oil-producing countries, agents can try to form a cartel like the Organization of Petroleum-Exporting Countries (OPEC).