Summary
Monetary policy affects aggregate demand through multiple transmission mechanisms. Key channels include the traditional interest-rate channel, which works by lowering the real cost of borrowing; asset price channels, such as the exchange rate, Tobin’s q, and wealth effects; and credit channels, including bank lending, balance sheet, cash flow, and household liquidity effects. Additionally, empirical evidence from episodes like the Great Recession and Japan’s lost decades highlight the importance of looking beyond short-term nominal interest rates. The four lessons derived emphasize the need to consider real interest rates, broader asset price movements, the potential effectiveness of policy at the zero lower bound, and the importance of price stability in guiding monetary policy.