This third edition continues the philosophy of the two earlier ones of presenting modern macroeconomics at a level appropriate to the intermediate course. The many revision were made largely to track important developments in the mainstream of macroeconomics. More than ever, macroeconomic research focuses on the fundamental determinants of output, employment, prices, and interest rates. These determinants are the economy’s technology, its blueprints for production – its labor farce, its capital stock, and its monetary policy. We stress the point that these forces set the basic levels of the key macro variables.