Glossary term

Game Theory

Game theory is the study of strategic decisions where each person's best choice depends on what others may do.

Updated

May 16, 2026

Read time

2 min read

What Is Game Theory?

Game theory is the study of strategic decisions where each person's best choice depends on what others may do. It is used in economics, business, investing, negotiations, politics, and everyday decision-making.

A “game” does not have to be playful. It can be any situation where players, choices, incentives, information, and outcomes interact.

Key Takeaways

  • Game theory studies strategic choices between people, firms, investors, or institutions.
  • The best decision may depend on how others respond.
  • It helps explain competition, cooperation, negotiation, pricing, and market behavior.
  • The prisoner's dilemma is one of the best-known game theory examples.
  • Game theory is useful, but real people may not behave with perfect information or perfect rationality.

How Game Theory Works

Game theory looks at the players, their possible choices, their incentives, and the outcomes attached to each combination of choices. A company deciding whether to cut prices, an investor deciding whether to sell, and a borrower negotiating with a lender can all be viewed through a strategic lens.

The point is not to predict the future perfectly. It is to ask a better question: “What might the other side do if I choose this?”

Common Game Theory Ideas

Idea

Plain-English meaning

Player

Someone making a strategic choice

Payoff

The outcome each player receives

Strategy

A plan for what to do under different conditions

Dominant strategy

A choice that works best regardless of what others do

Equilibrium

A situation where players have little reason to change choices

Why Game Theory Matters in Finance

Financial decisions often involve other decision-makers. Sellers respond to buyers. Competitors respond to price cuts. Markets respond to central banks. Investors respond to each other. Lenders respond to borrower behavior.

Game theory helps readers see those feedback loops. The decision is rarely isolated.

The Bottom Line

Game theory studies strategic choices where outcomes depend on what others do. In finance and business, it can make incentives, competition, cooperation, and market behavior easier to understand.

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