Frontiers of Business Cycle Research collects a number of papers that are standards on my graduate reading lists and some others that soon will be. It adds two lucid introductory papers, one by Thomas Cooley and Edward Prescott and another on computing by Gary Hansen and Prescott. The result is an excellent volume that will be invaluable to macroeconomic researchers and a stimulating introduction for graduate students. ert E. Lucas, Jr., The University of Chicago