This book combines a systematic empirical investigation into the characteristics of business cycles with a review of general theories of their patterns and dynamics. The authors have provided two empirical studies, using Swedish data for which unusually long data series are available. Both the empirical studies show how to analyse business cycles and to interpret them in the light of one well-established theoretical framework. The book's theoretical paper introduces readers to a different theoretical approach. The authors argue for the role played by shocks and by expectations in creating and exacerbating business cycles. As well as providing an overview of recent work in business cycle research, the book also shows how analytical techniques can be applied to historical data; it thus makes a substantial theoretical and applied contribution to the literature.