In this review article, I examine the relationship between trade policy and macroeconomic outcomes, focusing on how tariffs, trade barriers, and international policy changes affect aggregate prices, output, exchange rates, and welfare. The article was published in the Oxford Research Encyclopedia of Economics and Finance.

• Reviewed theoretical and empirical research on how trade policy affects macroeconomic outcomes.
• Synthesized evidence on tariff pass-through, exchange rate adjustment, welfare effects, and the interaction between trade policy and monetary policy.
• Connected micro-level evidence on firm and consumer responses to macroeconomic models of aggregate trade policy effects.
• Discussed how trade policy shocks can affect inflation, output, terms of trade, and international capital flows.
• Contributed a structured overview for researchers, students, and policy readers interested in the macroeconomic consequences of trade policy.