Unit 1 discusses international trade concepts like comparative advantage, protectionism, and developing countries' historical opposition to organizations like GATT. It includes readings and exercises on these topics. Unit 2 covers foreign direct investment, with readings defining terms like FDI and incentives. Exercises assess understanding of concepts like joint ventures. Unit 3 explains foreign exchange markets and transactions like hedging, arbitrage, and spot vs. forward rates. Readings define exchange rate systems and exercises test vocabulary. Unit 4 examines methods of international payment like letters of credit, collections, and advances. Readings provide details on documentation and exercises fill gaps in understanding payment processes.