In macrodynamics and business cycle analysis we find nowadays a variety of approaches elaborating frameworks for studying the fluctuations in economic and financial data. These approaches are viewed from Keynesian, monetarist and rational expectations standpoints. There are now also numerous empirical methods for the testing of nonlinear data generating mechanisms. This volume brings together a selection of contributions on theories of the business cycle and new empirical methods and synopsizes the new results. The volume (i) gives an overview of current models and modern concepts and tools for analyzing the business cycle; (ii) demonstrates, where possible, the relation of those models to the history of business cycle analysis; and (iii) presents current work, surveys and original work, on new empirical methods of studying cycle generating mechanisms.