The book traces the history of macroeconomics from Keynes to Lucas and beyond. It compares the Keynesian era with the Lucasian era, focusing on different methodological standards. In the Keynesian era, it looks at Keynesian macroeconomics, monetarism, and new Keynesian models. In the Lucasian era, it examines new classical macroeconomics, RBC modeling, and second-generation new Keynesian modeling. The book also explores alternative approaches to Lucasian macroeconomics. The author presents the information in a clear and critical way, emphasizing substantive assessments over technical details.